Lymphoscintigraphy and intraoperative lymphatic mapping of sentinel lymph nodes in melanoma patients. (41/1040)

Identification of sentinel lymph nodes (SLNs) using lymphoscintigraphy, the blue dye technique and intraoperative lymphatic mapping with a gamma-detecting probe has become the standard of care in diagnosing and treating melanoma. Numerous clinical studies have proven the reliability of predicting the histology of remaining lymph nodes in the lymphatic basin from the histologic evaluation of the SLNs. Technical and clinical factors presented in this paper have been shown to increase the accuracy of localization of SLNs. The nuclear medicine technologist shares a vital role in the radiopharmaceutical preparation and administration for preoperative lymphoscintigraphy and intraoperative lymphatic mapping in patients with melanoma.  (+info)

Video-assisted thoracoscopic surgery for spontaneous pneumothorax--a 7-year learning experience. (42/1040)

OBJECTIVES: To determine the effect of increasing experience of video-assisted thoracoscopic surgery (VATS) in the treatment of spontaneous pneumothorax (SP) on clinical efficacy and surgical practice. PATIENTS AND METHODS: A prospective study of 180 consecutive operations in 173 patients who underwent VATS for SP by a single surgeon during a 7 year period. RESULTS: 118 patients, mean age 32.1 years (range 13-63 years), were treated for primary spontaneous pneumothorax (PSP) while 55 patients, mean age 65.9 years (range 28-92 years), were treated for secondary spontaneous pneumothorax (SSP). All patients had VAT parietal pleurectomy combined in 162 (90%) patients with stapled bullectomy. At a current median experience of 2.0 years (range 0.4-6.8 years), 12 (6.6%) patients required reoperation for treatment failures within 12 months of surgery--9 patients within 30 days of VATS and 3 for late recurrent pneumothorax. Two patients (both with SSP) died within 30 days of surgery. When compared with PSP, VATS in SSP is characterized by an elderly, male predominance, a longer postoperative stay, a higher mortality rate and a lower rate of late recurrence. With increasing experience of the technique, there has been a significant decrease in treatment failures. In the treatment of PSP, both operating time and postoperative stay have decreased significantly with experience whilst the use of staple cartridges per patient has increased significantly with experience in both PSP and SSP. CONCLUSION: There is a demonstrable 'learning curve' effect on the clinical efficacy and surgical practice of video assisted thoracoscopic surgery for spontaneous pneumothorax.  (+info)

Perioperative heat balance. (43/1040)

Hypothermia during general anesthesia develops with a characteristic three-phase pattern. The initial rapid reduction in core temperature after induction of anesthesia results from an internal redistribution of body heat. Redistribution results because anesthetics inhibit the tonic vasoconstriction that normally maintains a large core-to-peripheral temperature gradient. Core temperature then decreases linearly at a rate determined by the difference between heat loss and production. However, when surgical patients become sufficiently hypothermic, they again trigger thermoregulatory vasoconstriction, which restricts core-to-peripheral flow of heat. Constraint of metabolic heat, in turn, maintains a core temperature plateau (despite continued systemic heat loss) and eventually reestablishes the normal core-to-peripheral temperature gradient. Together, these mechanisms indicate that alterations in the distribution of body heat contribute more to changes in core temperature than to systemic heat imbalance in most patients. Just as with general anesthesia, redistribution of body heat is the major initial cause of hypothermia in patients administered spinal or epidural anesthesia. However, redistribution during neuraxial anesthesia is typically restricted to the legs. Consequently, redistribution decreases core temperature about half as much during major conduction anesthesia. As during general anesthesia, core temperature subsequently decreases linearly at a rate determined by the inequality between heat loss and production. The major difference, however, is that the linear hypothermia phase is not discontinued by reemergence of thermoregulatory vasoconstriction because constriction in the legs is blocked peripherally. As a result, in patients undergoing large operations with neuraxial anesthesia, there is the potential of development of serious hypothermia. Hypothermic cardiopulmonary bypass is associated with enormous changes in body heat content. Furthermore, rapid cooling and rewarming produces large core-to-peripheral, longitudinal, and radial tissue temperature gradients. Inadequate rewarming of peripheral tissues typically produces a considerable core-to-peripheral gradient at the end of bypass. Subsequently, redistribution of heat from the core to the cooler arms and legs produces an afterdrop. Afterdrop magnitude can be reduced by prolonging rewarming, pharmacologic vasodilation, or peripheral warming. Postoperative return to normothermia occurs when brain anesthetic concentration decreases sufficiently to again trigger normal thermoregulatory defenses. However, residual anesthesia and opioids given for treatment of postoperative pain decreases the effectiveness of these responses. Consequently, return to normothermia often needs 2-5 h, depending on the degree of hypothermia and the age of the patient.  (+info)

Laparoscopic repair of perforated peptic ulcers. The role of laparoscopy in generalised peritonitis. (44/1040)

This non-randomised concurrent cohort study conducted in two teaching hospital Departments of Surgery examined the assumption that the benefits of elective laparoscopic upper gastrointestinal surgery would apply to those with generalised peritonitis due to perforated peptic ulcers. It compared 20 consecutive laparoscopic repairs of perforated peptic ulcers with a concurrent group of 16 consecutive open repairs. There were no differences pre-operatively between the two groups. The mean duration of surgery was similar (P = 0.46). There were no differences in the rate of GI tract recovery, but opiate analgesia requirement in the laparoscopic group was significantly less (P < 0.0001). Intensive care was required in three patients in the laparoscopic group (two with renal failure) and two in the open (no renal failure). Two patients in the laparoscopic and one in the open group died. The median duration of stay was five days in the laparoscopic group and six in the open. This comparison shows that the patho-physiological insult of laparoscopy in the setting of generalised peritonitis does not obviously increase the peri-operative risk of organ failure but objective benefits are small.  (+info)

The role of intraoperative radiation therapy (IORT) in the treatment of locally advanced gynecologic malignancies. (45/1040)

The prognosis in women with locally advanced primary or recurrent gynecologic malignancies is rather poor. Doses of external beam radiation necessary to treat gross or microscopic recurrence among patients surgically treated or previously irradiated exceed what is tolerated by normal structures. In this group of patients, intraoperative radiation therapy (IORT) can be utilized to maximize local tumor control, minimizing the radiation exposure of dose-limiting surrounding structures. Review of the available literature indicates that IORT may improve long-term local control and overall survival in women with pelvic sidewall and/or para-aortic nodal recurrence. The most encouraging results have been reported in the cases of microscopic residual disease, following surgical debulking.  (+info)

Elevated levels of soluble tumor necrosis factor receptors are associated with increased mortality rates in patients who undergo operation for ruptured abdominal aortic aneurysm. (46/1040)

PURPOSE: Elevated levels of soluble tumor necrosis factor receptors (sTNF-Rs) are associated with multiple organ failure and increased mortality rates in critically ill patients. Paradoxically, experimental data suggest exogenous sTNF-Rs may improve outcome in patients who undergo elective abdominal aortic aneurysm (AAA) repair. This study examines, for the first time, changes in sTNF-R levels during repair of ruptured and nonruptured AAA. METHODS: Sixteen patients who underwent surgical procedures for ruptured AAA and 10 patients who underwent surgical procedures for nonruptured AAA were studied. Levels of sTNF-Rs p55 and p75 were measured before the operation and immediately before and 5 minutes, 6 hours, and 24 hours after aortic clamp release. RESULTS: When compared with nonruptured AAA, levels of sTNF-R p55 were significantly higher in ruptured AAA 5 minutes (P <.02) and 24 hours after aortic clamp release (P <.05). Levels of sTNF-R p75 were significantly higher in ruptured AAA before (P <.05), during (P <.001), and after the surgical procedure (P <.01). Six hours after aortic clamp release, sTNF-R p75 levels were significantly higher in nonsurvivors of ruptured AAA when compared with survivors (P <.05) and patients who underwent surgical procedures for nonruptured AAA (P <.01). CONCLUSION: Ruptured AAA repair is associated with increased sTNF-R expression. Furthermore, elevated levels of sTNF-R p75 are associated with increased postoperative mortality rates.  (+info)

Endotoxemia during supraceliac aortic crossclamping is associated with suppression of the monocyte CD14 mechanism: possible role of transforming growth factor-beta1. (47/1040)

PURPOSE: Monocyte CD14 and its soluble form (sCD14) mediate the proinflammatory response to endotoxemia. The aim of this study was to measure the changes to these factors after major aortic surgery and the possible inhibitory role of transforming growth factor-beta(1) (TGF-beta(1)) during these procedures. METHODS: Twenty-four patients with supraceliac aortic crossclamping during thoracoabdominal aortic aneurysm (TAAA) repair and 12 patients with infrarenal aortic crossclamping as part of infrarenal aneurysm repair (AAA) were studied. Blood was collected at incision, aortic clamping, and reperfusion and at 1, 8, and 24 hours after reperfusion. Samples were assayed for endotoxin, peripheral blood monocyte CD14 expression, sCD14, tumor necrosis factor-alpha, and TGF-beta(1). RESULTS: Although there was significant endotoxemia on reperfusion in both groups of patients, peak plasma endotoxin levels were significantly higher in patients with TAAA (P =.001). Monocyte CD14 and plasma sCD14 were significantly decreased in patients with TAAA at reperfusion and 1 hour after reperfusion (P <.01, both points). In patients with AAA, a significant upregulation of CD14 was observed at 24 hours after reperfusion (P <.01), but no significant changes in sCD14 were observed. TNF-alpha showed no significant changes during the study period in both groups. In patients with TAAA, TGF-beta(1) showed significant elevation at all time points (P <.01); whereas in patients with AAA, TGF-beta(1) showed no significant changes. CONCLUSION: Splanchnic ischemia reperfusion in patients who undergo supraceliac aortic clamping is associated with peripheral blood monocyte CD14 suppression and significant elevation of TGF-beta(1). TGF-beta(1) may play an important role in modulating the immune response to endotoxemia during major aortic aneurysm surgery.  (+info)

Changes in intravascular volume during acute normovolemic hemodilution and intraoperative retransfusion in patients with radical hysterectomy. (48/1040)

BACKGROUND: Changes in blood volume during acute normovolemic hemodilution (ANH) and their consequences for the perioperative period have not been investigated sufficiently. METHODS: In 15 patients undergoing radical hysterectomy, preoperative ANH to a hematocrit of 24% was performed using 5% albumin solution. Intraoperatively, saline 0.9% solution was used for volume substitution, and intraoperative retransfusion was started at a hematocrit of 20%. Plasma volume (indocyanine green dilution technique), hematocrit, and plasma protein concentration were measured before and after ANH, before retransfusion, and postoperatively. Red cell volume (labeling erythrocytes with fluorescein) was determined before and after ANH and postoperatively. RESULTS: Mean normal plasma volumes (1,514 +/- 143 ml/m2) and reduced red cell volumes (707 +/- 79 ml/m2) were measured preoperatively. Blood (1,150 +/- 196 ml) was removed and replaced with 1,333 +/- 204 ml of colloid. Blood volume before and after ANH was equal and amounted to 3,740 ml. Intraoperatively, plasma volume did not increase until retransfusion despite infusing 3,389 +/- 1,021 ml of crystalloid (corrected for urine output) to compensate for an estimated surgical blood loss of 727 +/- 726 mi. Postoperatively, after retransfusion of all autologous blood, blood volume was 255 +/- 424 ml higher than preoperatively before ANH. Despite mean calculated blood loss of 1,256 +/- 892 ml, only one patient received allogeneic blood. CONCLUSIONS: During ANH, normovolemia was exactly maintained. After surgical blood loss of 1,256 +/- 892 ml, crystalloid and colloid supplies of 5,752 +/- 1,462 ml and 1,667 +/- 548 ml, respectively, and complete intraoperative retransfusions of autologous blood in every patient, mean blood volume was 250 ml higher than preoperatively before ANH.  (+info)