Total parenteral nutrition: techniques, complications, and prevention

During the past half century, surgeons have demonstrated the greatest interest and have made the most concerted effort in developing innovative, comprehensive, and effective methods for providing adequate nutritional support to patients in the widest range of clinical conditions and situations. Several factors account for the continual stimulation of thoughtful surgeons and physicians to maintain or improve the nutritional status of their patients.

Nd:YAG laser surgery for the excision of pilonidal cysts: a comparison with traditional techniques

BACKGROUND AND OBJECTIVE

Nd:YAG laser photothermal ablation has been accepted as a treatment modality for hemorrhoidal disease. There is little reported on its use in treating pilonidal disease. We hypothesized that laser would be an excellent tool for pilonidal cystectomy, facilitating improved outcome and patient satisfaction.

STUDY DESIGN/MATERIALS AND METHODS

A 5-year retrospective study was performed comparing Nd:YAG laser to the standard surgical technique. A telephone questionnaire addressing the length of time the cyst was debilitating both preoperatively and postoperatively as well as length of convalescent time before return to work was administered. Pain was assessed by using an analog pain scale.

RESULTS

Operative time for the traditional pilonidal cystectomy was 20 minutes longer than Nd:YAG laser cystectomy. Postoperative hospital stay was similar. Laser patients returned to work an average of 2.4 days earlier, and their postoperative pain was less than those treated traditionally.

CONCLUSION

In an era when the medical consumer makes decisions based on the efficacy of treatment by using criteria such as pain, length of hospitalization, and speed of return to work, Nd:YAG lasers have emerged as a surgical tool that can fulfill these criteria for certain procedures. Patient postoperative satisfaction after laser excision was greater when compared with those who had traditional excisions. Postoperative pain was less, as was the pain experienced during the first week of recovery. Cost for both was comparable.

Use of the Nd-YAG laser improves quality of life and economic factors in the treatment of hemorrhoids

PURPOSE

Hemorrhoidal disease may benefit from the use of Nd-YAG laser to decrease surgical recovery time, postoperative hospital stay and complications.

METHODS

Fifty patient charts from 1993 to 1998 were reviewed retrospectively to evaluate postoperative complications and overall patient satisfaction following hemorrhoidectomy. We used the Nd-YAG laser from Surgical Laser Technologies CL60 with the ERP4 sapphire tip and the setting of 20 watts on continuous wave mode. Coagulation posthemorrhoidal excision of the remaining tissue was done using 60 watts pulse wave setting of 0.3 seconds.

RESULTS

Laser treated hemorrhoidectomy patients experienced less pain than the standard hemorrhoidectomy patients. One week after surgery, the laser treated patients had 65% less pain than the standard hemorrhoidectomy patients. Painless defecation occurred earlier in the laser treated patients by five days and postoperative drainage was less than standard surgically treated patient. Surgical and hospital costs were lower by 27% and 11% respectively in the laser treated group. 88% of the laser treated patients vs 44% of the standard patients resumed work at one week after surgery.

CONCLUSIONS

Nd-YAG laser treated hemorrhoid surgery patients had a quicker recovery and earlier return to work.

The double-crush phenomenon--an unusual presentation and literature review

The double-crush syndrome was initially described by Upton and McComas in 1973. They postulated that nonsymptomatic impairment of axoplasmic flow at more than one site along a nerve might summate to cause a symptomatic neuropathy. This was suggested by their clinical observation that the majority of their patients had a median or ulnar neuropathy associated with evidence of cervicothoracic root lesions. They also hypothesized that one of the constraints on axoplasmic flow could be a metabolic neuropathy, and this is supported by the high association of diabetes and carpal tunnel syndrome. Other researchers have since reported series of patients supporting the frequent association of a proximal and distal nerve compression syndrome, including carpal tunnel syndrome associated with cervical radiculopathy, brachial plexus compression, and diabetic neuropathy. Subsequently, MacKinnon and Dellon have expanded the description of this syndrome to include a) multiple anatomic regions along a peripheral nerve, b) multiple anatomic structures across a peripheral nerve within an anatomic region, c) superimposed on a neuropathy, and d) combinations of the above. We present an unusual case of symptomatic nerve compression caused by two nonanatomic structures within an anatomic region.

Ischemic preconditioning improves the survival of skin and myocutaneous flaps in a rat model

Inadequate blood supply of pedicle flaps results in partial necrosis, and prolonged ischemia during free-tissue transfer can result in partial or complete flap necrosis. Recent research in the field of cardiovascular surgery has shown that ischemic preconditioning (repeated brief episodes of coronary artery occlusion followed by reperfusion) improves myocardial muscle survival when the heart is subsequently subjected to prolonged ischemia. Preconditioning of skin or myocutaneous flaps as either pedicle or free flap models has never been studied. The goal of this investigation was to measure the effect of ischemic preconditioning on myocutaneous and skin flap survival areas and total necrosis rates after variable periods of global ischemia. In 220 rats, 100 transverse rectus abdominis myocutaneous flaps and 120 dorsal cutaneous flaps were randomized into treatment and control groups. The treatment flaps underwent preconditioning by three cycles of 10 minutes of pedicle clamping followed by 10 minutes of reperfusion for a total preconditioning period of 1 hour. The control flaps were perfused without clamping for 1 hour. Both control and treatment flaps then underwent global ischemia for 0, 2, 4, 6, 10, or 14 hours by pedicle clamping. Flap survival area was measured on the fifth postoperative day. Statistical analysis was performed with analysis of variance, student's t tests, and probit analysis. Preconditioning improved survival areas of pedicle myocutaneous flaps (0-hour group) from 47 +/- 16 percent (mean percent area surviving +/- SD) to 63 +/- 5 percent. This difference was statistically significant (t test, p < 0.04). There was no statistically significant improvement in pedicle skin flap survival. For free flap models (flaps undergoing global ischemia), preconditioning increased the survival areas of skin and myocutaneous flaps (analysis of variance, p < 10(-5)). For the skin flap model, statistical significance of the survival area difference was reached at 6, 10, and 14 hours of ischemia (t test, p < 10(-4)). The magnitude of this effect was higher in the myocutaneous flap model and reached statistical significance at 2, 4, 6, and 10 hours of ischemia (p < 10(-3)). Preconditioned flap survival areas were increased by two to five times that of non-preconditioned flaps at these ischemia times. Preconditioning lowered total necrosis rates at all ischemia times for both flap models. The critical ischemia time when 50 percent of skin flaps became totally necrotic (CIT50) improved from 6.9 to 12.4 hours by preconditioning. Similarly, preconditioning improved the CIT50 of myocutaneous flaps from 3.6 to 9.2 hours. For the first time, statistically significant improvements of partial necrosis areas and total necrosis rates have been demonstrated through intraoperative ischemic preconditioning of skin and myocutaneous flaps. In clinical practice, application of this technique may lead to improved survival during pedicled or free transfer of myocutaneous flaps and free transfer of skin flaps.

Ischemic preconditioning of musculocutaneous flaps: effects of ischemia cycle length and number of cycles

Previous work in our laboratory has indicated that ischemic preconditioning improves musculocutaneous flap survival 2.5 times that of the control flap area when the flaps are subsequently subjected to 4 hours of global ischemia. The preconditioning protocol used in this study was arbitrarily designed to be 10 minutes of pedicle clamping followed by 10 minutes of reperfusion. This sequence was repeated for three cycles with a total preconditioning time of 1 hour. There are no published works comparing different preconditioning protocols in musculocutaneous flaps. The goal of this study was to determine if the ischemic cycle time and the number of cycles influenced the effectiveness of ischemic preconditioning. Fifty-one male Sprague-Dawley rats were divided into one control and six treatment groups of 6 to 10 animals in each group. A transverse rectus abdominis musculocutaneous flap based on the inferior epigastric vessels was elevated in each animal. Flaps were preconditioned by pedicle clamping and reperfusion for either 5 or 10 minutes per cycle. This was repeated for one, two, or three cycles. Controls were simply perfused for 30 minutes. Each flap was then subjected to 4 hours of global ischemia. Flap surface survival area was calculated on the fifth postoperative day by computerized video planimetry. Differences in survival areas between control and preconditioned flaps were compared using analysis of variance and t-tests. There was an overall statistical significance in the comparison of flap survival of preconditioned flaps with that of controls. A single 5-minute cycle improved flap survival 2.5 times the mean control area. Two and three 5-minute cycles resulted in a reduction of the preconditioning effect, with flap survival no different than controls. Ten-minute preconditioning cycles increased flap survival 1.5 to 3 times the mean control area. Flap survival was improved by increasing the number of 10-minute cycles. Cycle time and number of cycles have definite effects on the survival areas of preconditioned musculocutaneous flaps. Ischemic preconditioning with 10-minute cycles is superior to 5-minute cycles. Three cycles of 10-minute preconditioning is statistically superior to one or two cycles. Future studies are planned to study four or more cycles and longer cycle times.

Comparison of the effects of ischemic preconditioning and surgical delay on pedicled musculocutaneous flap survival in a rat model

Both surgical delay (SD) and ischemic preconditioning (IP) have been shown to be effective in improving the survival of pedicled musculocutaneous flaps. The goal of our study was to determine the effects of IP and SD, separately and together, on the survival of pedicled transverse rectus abdominis musculocutaneous (TRAM) flaps in a rat model. Thirty-two male Sprague-Dawley rats were divided into four groups of 8 rats each: (1) control, (2) 2-week SD, (3) IP, and (4) SD plus IP. A TRAM flap was elevated in each rat. Flap viability was assessed on the fifth postoperative day by computerized video planimetry. Mean area of flap survival was compared between the control, IP, SD, and SD plus IP groups using analysis of variance and Student's t-test. Improvement in surface area survival was seen in musculocutaneous flaps subjected to IP, SD, and SD plus IP compared with the control. IP and SD improved survival 1.3 and 1.4 times the control area respectively. Differences between treatment and control flaps were statistically significant (p < 0.04). In addition, the combination of SD plus IP improved survival by 1.8 times, which is statistically different from controls and from either technique individually (p < 0.002). IP and SD have similar efficacy in improving survival in this musculocutaneous flap model. The effects of IP and SD appear to be additive. The advantage of IP over SD is that IP can be performed during the same operative session as the flap elevation and only adds 1 hour to the surgical procedure.

Trends in the incidence of upper extremity soft tissue malignancies: a 40-year review of the Connecticut State Tumor Registry

BACKGROUND

Although soft tissue malignancies of the upper extremity are rare, the management of these lesions has been controversial and the etiologic factors associated with the occurrence of these tumors are not well understood. The purpose of this study was to identify possible epidemiologic factors related to a recently noted rise in the occurrence of these tumors in the state of Connecticut.

METHODS

The occurrence of upper extremity soft tissue tumors over the past 40 years was reviewed in the Connecticut State Tumor Registry. Demographic data collected included occupational history, residence, and presence of concomitant malignancies. Tumor histology, the extent of resection, and the incidence of recurrences were also noted. Factors associated with recurrence were identified using linear regression analysis.

RESULTS

During the 40-year study period, 359 patients having upper extremity soft tissue tumors were entered into the Connecticut State Tumor Registry. An increasing trend in the number of upper extremity soft tissue tumors was evident. Many patients were involved in heavy industry or related fields. Fibrosarcoma and liposarcoma were the most common tumor types, occurring in 111 (30.3%) and 48 patients (13.2%), respectively. Sixty-seven patients presented with a synchronous second primary malignancy of the breast (49 patients), lung (seven patients), or gastrointestinal tract (five patients). Most patients (69.9%) underwent local excision of the soft tissue tumors, with fewer undergoing wide excision (20.3%) or radical excision (9.7%). Recurrence, which occurred in 144 patients, was found to be associated with extent of resection, occupational history, and concomitant malignancy. Delineation of such risk factors may be helpful in identifying patients in whom aggressive management may decrease recurrence and improve survival.

Distal dorsal forearm flap

The goal of this study was to investigate the vascular supply of the distal dorsal forearm and the feasibility of using a local skin flap based on perforating vessels of the anterior interosseous artery (AIA) to reconstruct the dorsal aspect of the hand. The results of anatomic studies on 71 adult, fresh-frozen cadaveric upper extremities indicate that a new flap can be designed based on a cutaneous branch of the AIA. The AIA runs along the volar surface of the anterior interosseous membrane. At the proximal border of the pronator quadratus muscle it gives off a dorsal septocutaneous branch (DSCB) that pierces the interosseous membrane and supplies the extensor muscles of the thumb and the skin of the distal two-thirds of the dorsal forearm. The average artery diameter at the origin of the DSCB was 1.1 +/- 0.2 mm (mean +/- standard error of mean). The mean pedicle length was 3.1 +/- 0.6 cm. The pedicle could be extended to 12.4 +/- 0.9 cm if the entire AIA was included. Based on dye injection studies, the smallest skin paddle that could be supported by this vessel ranged from 5 x 9 cm to 8 x 15 cm. The flap can be configured as an island vascular flap based on the DSCB or AIA, a distally based flap, a free flap, a fascial flap, or a composite flap including muscle, bone, nerve, and skin.