Effects of super-pulsed Nd-YAG laser on arterial tissue: comparison with continuous wave

The effects of a super-pulsed Nd-YAG laser at 1.32 μm wavelength on normal or atherosclerotic human arterial tissue were evaluated and compared with those obtained with continuous wave. One joule per pulse was delivered through a 0.2 mm optical fibre with a pulse width of 10 ms at 10 Hz (super-pulse), or 10 W (10 J) were delivered at continuous wave in saline or blood. Ten joules were delivered with super-pulse or continuous wave for each tissue specimen. The aortic specimens were lased either by continuous wave or super-pulse. At super-pulse mode, ablation efficiency (mm³ J⁻¹) was 0.0149±0.0044 for normal tissue in saline, 0.0148±0.0043 for atheroma in saline, 0.0138±0.0062 for normal tissue in blood, and 0.0146±0.0049 for atheroma in blood. There was no significant difference between the groups. At continuous wave mode, ablation efficiency was 0.0507±0.0299 for atheroma in blood (p<0.001 vs super-pulse). However, extensive charring was observed with continuous wave lasing (41% with continuous against 14% with pulsed mode,p<0.001). Heavily calcified plaques were also ablated at 1.5 J per pulse and 15 W (continuous wave), resulting in extensive charring with continuous wave (77% vs 18% with super-pulse,p<0.01). In conclusion, at super-pulse mode, 1.32 μm Nd-YAG laser has neither the selectivity for atheroma nor influence of blood, thermal injury induced by super-pulse is less than that induced by continuous wave (cw), calcified plaques can be ablated by super-pulse, and super-pulsed Nd-YAG laser angioplasty is safer to use than continuous wave.     

A comparison of photosensitizer administration routes for interstitial photodynamic therapy of the liver

Accurate localization of laser light within a tumour lessens the need for selective tumour retention of the photosensitizer. The aim of this study was to investigate different routes of photosensitizer administration for interstitial photodynamic therapy (IPDT) of the liver. Sprague-Dawley rats were photosensitized with HPD 5 mg kg⁻¹ intravascularly at 48 h or by regional administration 60 min prior to light delivery or by interstitial injection (0.04 mg, 0.15 ml) directly into the hepatic parenchyma at 10 and 60 min prior to light delivery. Thirty-two joules of light from a helium-neon (HeNe) laser were delivered interstitially into the median lobe of the liver via a 200-μm optical fibre. Four days after light delivery the liver was harvested, sectioned and stained with haematoxylin and eosin (HE). The maximum cross-sectional area of photodamage was estimated for each photosensitizer administration route in six livers. Both conventional PDT and interstitial routes of administration of the photosensitizer showed comparable areas (±s.e.m.) of bioactivity (8.32±2.03 mm² and 9.5±1.44 mm²) that were greater than those for control livers treated with light only (1.89±0.39 mm²,p<0.01). The maximum area of biological effect was noticed in livers regionally photosensitized by the portal vein or hepatic artery 60 min prior to light delivery (intraportal vein 13.32±1.52 mm² and intrahepatic artery 14.21±4.19 mm²,p<0.01). These results suggest that for IPDT, regional administration of a photosensitizer may achieve the greatest biological effect. This route may be the most appropriate route for interstitial PDT using a selective light delivery system within the liver.     

Production and systemic absorption of toxic byproducts of tissue combustion during laparoscopic surgery

Background: Among the potential hazards of laparoscopic surgery using electrocautery is the intraperitoneal release and subsequent absorption of byproducts of tissue combustion. In a porcine model of laparoscopic surgery with smoke production, our aims were to assess (1) the relationship between levels of intraperitoneal carbon monoxide (CO) and systemic carboxyhemoglobin (COHb) and methemoglobin (MetHb), and (2) intraperitoneal concentrations of other noxious gases, including hydrogen cyanide (HCN), acrylonitrile (Acr), and benzene (Bzn). Methods: Seven pigs underwent laparoscopic resection of three hepatic wedges using monopolar electrocautery in a CO₂ pneumoperitoneum. Sequential arterial samples were drawn to measure [COHb] and [MetHb] perioperatively, while gaseous intraabdominal [CO], [HCN], [Acr], and [Bzn] were assayed intraoperatively. Results: The mean ± SEM duration of operation was 90 ± 2 min, and electrocautery was used for 68 ± 4 min. Intraabdominal [CO] rose from 0 to 814 ± 200 ppm (p < 0.01) while [COHb] increased from 2.9 ± 0.1% to 3.5 ± 0.1% (p < 0.001). Systemic [MetHb] remained unchanged intra- and postoperatively, ranging from 0.3 to 0.7%. Intraperitoneal [HCN] rose from 0 to 5.7 ± 0.7 ppm (p < 0.001). [Acr], however, did not change significantly from preoperative values, ranging from 0 to 1.6 ± 1.0 ppm, and [Bzn] was undetectable. Conclusions: Laparoscopic tissue combustion increases intraabdominal [CO] to ``hazardous' levels leading to minimal, yet significant, elevations of [COHb]. Systemic [MetHb] and intraabdominal [HCN], [Acr], and [Bzn] are not elevated to toxic levels. Production of intraperitoneal smoke during laparoscopic electrosurgery therefore may not pose a significant threat to the patient. Received: 3 April 1997/Accepted: 22 May 1997     

Hepatocellular Glycogen in Alleviation of Liver Ischemia-Reperfusion Injury During Partial Hepatectomy

Background Temporary occlusion of liver blood supply for complex liver operation is common in liver surgery. However, hepatic vascular occlusion will undoubtedly impair liver function. This study was designed to elucidate the effect of hepatocellular glycogen in alleviation of liver ischemia-reperfusion injury during hepatic vascular occlusion for partial hepatectomy. Methods Fifty-seven patients were randomly divided into an experimental group (n = 29) and a control group (n = 28). In the experimental group, patients were given high-concentration glucose intravenously during 24 h before the operation. The hepatic lesion was resected after portal triad clamping in the two groups. Noncancer liver tissue was biopsied to measure hepatic tissue ATP content and change of malondialdehyde (MDA) and superoxide dismutase (SOD). Liver function of all patients was assessed by using an automatic biochemical analysis apparatus before the operation and the first and fifth days after operation. Results The mean hepatic vascular occlusion time in the experimental group was 19.21 ± 4.54 min and in the control group it was 21.04 ± 5.11 min. Hepatic tissue ATP content of the experimental group was significantly higher than that of the control group at the end of hepatic vascular occlusion (2.15 ± 0.39 μmol/g wet tissue vs. 1.33 ± 0.44, p < 0.01) and at the point of 1-h reperfusion (2.19 ± 0.29 μmol/g wet tissue vs. 1.57 ± 0.35, p < 0.01). There was significant difference in SOD activity between the two groups at the end of hepatic vascular occlusion (130.69 ± 30.49 NU/mg pr vs. 97.83 ± 26.23, p < 0.01) and at the point of 1-h reperfusion (139.55 ± 39.88 NU/mg pr vs. 114.74 ± 25.93, p < 0.01). Significant difference was shown in MDA content between the two groups at the end of hepatic vascular occlusion (3.02 ± 0.30 nmol/mg pr vs. 3.99 ± 0.49, p < 0.01) and at the point of 1-h reperfusion (3.81 ± 0.69 nmol/mg pr vs. 5.75 ± 1.17, p < 0.01). In addition, the liver function of the experimental group was significantly better than that of the control group the first and fifth days after the operation (p < 0.01). Conclusions Abundant intracellular glycogen may reduce liver ischemia-reperfusion injury caused by hepatic vascular occlusion. It is beneficial to give a large amount of glucose before a complex liver operation during which temporary occlusion of hepatic blood flow is necessary.     

Effect of CO2 Pneumoperitoneum on Growth of Liver Micrometastases in a Rabbit Model

Little is known about the risk of metachronous liver metastases following laparoscopic resection for gastrointestinal malignancies. The effect of CO₂ pneumoperitoneum on the growth of established liver micrometastases was investigated in a rabbit model. Male Japanese white rabbits weighing 2.8 to 3.3 kg were randomized to three groups (n= 15 per group) 3 days following intraportal inoculation of a tumor suspension containing 5 × 10⁴ cells of VX₂ cancer. In the pneumoperitoneum group, insufflation with CO₂ was maintained at a pressure of 10 mmHg for 30 minutes. In the laparotomy group the abdominal cavity remained open through a 45 mm midline incision for 30 minutes; in the control group no treatment other than anesthesia was performed. Cancer nodules on the liver surface were compared among the three groups on day 17. There was no difference in the number of cancer nodules among the groups (p= 0.72). A significant difference in the total area of cancer nodules (mean ± SEM) was found only between the pneumoperitoneum group (696.0 ± 177.0 mm²) and the control group (247.2 ± 60.7 mm²) (p < 0.05). The frequency of cancer nodules larger than 3.0 mm in maximal diameter tended to be highest in the pneumoperitoneum group (p= 0.053). These results suggests that CO₂ pneumoperitoneum may promote the growth of established liver micrometastases in this animal model.     

Injury and adhesion formation following ovarian wedge resection with different thermal surgical modalities

The purpose of this study is to determine the role of bleeding, acute thermal damage, and charring in adhesion formation. Postoperative adhesions were compared following ovarian wedge resection in 48 rabbits using different lasers, electrosurgery, and scalpel. Twelve ovaries were sectioned per modality, in randomized pairs. Acute thermal injury as assessed by histology, bleeding, and charring differed amonge the modalities used. Adhesions were assessed 4 weeks later, by an investigator completely blinded of the treatment protocol. The adhesion scores were 11.6 ± 8.0 with pulsed Er:YAG laser; 11.9 ± 7.5 with scalpel; 8.3 ± 9.3 with electrocautery; 6.7 ± 8.8 with a continuous (c.w.) Nd:YAG laser; 5.3 ± 4.8 with c.w. CO₂ laser; 3.1 ± 2.7 with pulsed CO₂ laser; 1.7 ± 1.8 with pulsed Ho:YAG laser; and 0.8 ± 1.5 in the control (no resection) group. Ho:YAG, Nd:YAG, and electrocautery were completely hemostatic. Bleeding was minimal with the CO₂ lasers. Er:YAG and scalpel caused maximum bleeding, requiring hemostatic measures to prevent exanguination. Charring occurred with electrocautery, CO₂ laser, and Nd:YAG laser. Bleeding and charring correlated with adhesion formation, but the histological depth of thermal damage did not. The Ho:YAG laser is a hemostatic, fiber-optic compatible laser causing significantly fewer adhesions (P<0.04) than scalpel, electrocautery, Nd:YAG, Er:YAG, and c.w. CO₂ lasers. Clinical use of the Ho:YAG laser, and the role of carbonization in promoting adhesions, deserve further study. © 1993 Wiley-Liss, Inc.     

Volumetric and Functional Recovery of the Remnant Liver After Major Liver Resection with Prior Portal Vein Embolization

Introduction  Portal vein embolization is an accepted method to increase the future remnant liver preoperatively. The aim of this study was to assess the effect of preoperative portal vein embolization on liver volume and function 3 months after major liver resection. Materials and methods  This is a retrospective case-control study. Data were collected of patients who underwent portal vein embolization prior to (extended) right hemihepatectomy and of control patients who underwent the same type of resection without prior portal vein embolization. Liver volumes were measured by computed tomography volumetry before portal vein embolization, before liver resection, and 3 months after liver resection. Liver function was assessed by hepatobiliary scintigraphy before and 3 months after liver resection. Results  Ten patients were included in the embolization group and 13 in the control group. Groups were comparable for gender, age, and number of patients with a compromised liver. The mean future remnant liver volume was 33.0 ± 8.0% prior to portal vein embolization in the embolization group and 45.6 ± 9.1% in the control group (p < 0.01). Prior to surgery, there were no significant differences in future remnant liver volume and function between the groups. Three months postoperatively, the mean remnant liver volume was 81.9 ± 8.9% of the initial total liver volume in the embolization group and 79.4 ± 11.0% in the control group (p > 0.05). Remnant liver function increased up to 88.1 ± 17.4% and 83.3 ± 14% respectively of the original total liver function (p > 0.05). Conclusion  Preoperative portal vein embolization does not negatively influence postoperative liver regeneration assessed 3 months after major liver resection. No grant support. Paper presented at the SSAT, Chicago, June 1, 2009.     

Glycine Pretreatment Ameliorates Liver Injury After Partial Hepatectomy in the Rat

ABSTRACT

Background: Living donor liver transplantation subjects the donor to a major hepatectomy. Pharmacological or nutritive protection of the liver during the procedure is desirable to ensure that the remnant is able to maintain sufficient function. The aim of our study was to analyze the effects of pretreatments with α-tocopherol (vitamin E), the flavonoid silibinin and/or the amino acid L-glycine on the donor in a rat model. Methods: Male Wistar rats were pretreated with L-glycine (5%% in chow, 5 days), α-tocopherol (100 mg/kg body weight by gavage, 3 days) and/or silibinin (100 mg/kg body weight, i.p., 5 days). Thereafter, 90%% partial hepatectomy was performed without portal vein clamping. Results: Glycine pretreatment markedly decreased transaminase release (AST, 12 hr: glycine 1292 ± 192 U/L, control 2311 ± 556 U/L, p < .05; ALT, 12 hr: glycine 1013 ± 278 U/L, control 2038 ± 500 U/L, p < .05), serum ALP activity and serum bilirubin levels (p < .05). Prothrombin time was reduced, and histologically, liver injury was also decreased in the glycine group. Silibinin pretreatment was less advantageous and pretreatment with α-tocopherol at this very high dose showed some adverse effects. Combined, i.e., triple pretreatment was less advantageous than glycine alone. Liver resection induced HIF-1α accumulation and HIF-1α accumulation was also decreased by glycine pretreatment. Conclusion: The decrease of liver injury and improvement of liver function after pretreatment with glycine suggests that glycine pretreatment might be beneficial for living liver donors as well as for patients subjected to partial hepatectomy for other reasons.     

An experimental study on the effects of the steel scalpel,electrocautery and various lasers on oral tissue

The tissue effects of the steel scalpel, electrocautery, CO₂ laser and contact Nd-YAG laser were studied on rat tongue. The tip of the tongue (3 mm) was cut off and fixed for histology. The rats (6-10/method/age group) were kept alive for 2, 7 and 14 days, when the remaining tongue was resected. In each postoperative age group the effects to the epithelium and muscular layer were determined separately. Peroperative bleeding was measured and attention was paid to wound contraction and inflammatory cell infiltration.Postoperative bleeding occurred with the steel scalpel and electrocautery, but not with the lasers. A significant delay in early re-epithelialization was observed after the use of all thermal knives. Resection with steel scalpel was found to result in the smallest damage to the tissues on day 0 (P< 0.01), whereas on day 7 no significant differences were observed between scalpel, electrocautery and CO₂ laser. On the other hand there was a significant difference between scalpel and contact Nd-YAG laser (P< 0.05). On day 14 these differences were no longer significant.Wound contraction on days 7 and 14 was evident after scalpel incision and slight after thermal knives.The steel scalpel causes less tissue damage than the thermal knives, whereas the advantages of a bloodless operation can be achieved with both lasers used in this study.     

Procedures of Choice for Resection of Primary and Recurrent Liver Metastases from Colorectal Cancer

Although liver resection offers the only realistic chance of cure for patients with liver metastases from colorectal cancer, no consensus exists as to the procedure of choice for managing these tumors. Data from 193 patients who underwent hepatectomy for liver metastases from colorectal cancer and 26 of 193 patients who underwent repeat hepatectomy for recurrent metastases were collected. The suitability of resection was evaluated retrospectively based on known risk factors for recurrence and patterns of recurrence. On multivariate analysis, a positive surgical margin (SM+) was the only risk factor for recurrence after the initial resection (p < 0.01). SM+ (p < 0.01) and nonanatomic resection (p < 0·05) that was less than a sectionectomy (p < 0.05) were risk factors for recurrence after repeat hepatectomy. Multiple tumors (four or more) was the most common pattern of recurrence after initial hepatectomy, and recurrence close to the line of resection was most common after repeat hepatectomy. Based on tumor doubling times, recurrence after initial hepatectomy seemed to originate from the primary colorectal lesion, whereas recurrence after repeat hepatectomy was derived from a hepatic metastasis. Retrospective analysis suggests that hepatectomy with clear surgical margins is more important than anatomic resection for initial hepatectomy, and at least sectionectomy is necessary for repeat hepatectomy.     

Comparison of laparoscopic versus open liver tumor resection: a case-controlled study

Background  Although there are data in the literature about the safety and efficacy of laparoscopic liver resections, there are not many studies comparing laparoscopic versus open approaches in a case-matched design. The purpose of this study is to compare the perioperative outcome of laparoscopic versus open liver resections from a single institution. Methods  Thirty-one patients underwent laparoscopic liver resection between April 1997 and August 2007, with a prospective laparoscopic program started in April 2006 (n = 25). This group of patients was compared with 43 consecutive patients undergoing open resection who were matched by size of the lesion (5 cm or less for malignant and 8 cm or less for benign), anatomical location (segments 2, 3, 4b, 5, 6), and type of resection (wedge resection, segmentectomy, partial liver resection). Data were obtained from medical records as well as from a prospective database. Statistical analysis was performed using t-test and chi-square. All data are expressed as mean ± standard error on the mean (SEM). Results  Mean age in the laparoscopic group was 57.6 ± 2.7 years versus 61.9 ± 2.3 years in the open group (p = 0.2). There were more women in the laparoscopic group [74% females (n = 23) and 26% males (n = 8)] versus in the open group [40% females (n = 17) and 60% males (n = 26)] (p = 0.003). There were more patients with malignant lesions in the open group (73%) versus in the laparoscopic group (45%) (p = 0.01). Eight patients underwent partial and 23 patients segmental/wedge liver resection in the laparoscopic group versus 15 patients who underwent partial and 28 patients segmental/wedge liver resection in the open group (p = 0.7). Mean tumor size was 3.9 ± 0.4 cm in the laparoscopic group versus 4.2 ± 0.3 cm in the open group (p = 0.5). Ten (32%) out of 31 cases in the laparoscopic group were hand-assisted. Inflow occlusion was used in 1 case (3%) in the laparoscopic group versus 16 (37.2%) in the open group. Mean operating time was 201 ± 15 min for the laparoscopic group and 172 ± 12 min for the open group (p = 0.1). Mean estimated blood loss during the procedure was 122.5 ± 45.4 cc for the laparoscopic group and 299.6 ± 33.6 cc for the open group (p = 0.002). Surgical margin was similar for malignant cases in both groups. Mean hospital stay was 3.2 ± 1.0 days for the laparoscopic group and 6.8 ± 0.7 days for the open group (p = 0.004). The incidence of postoperative complications was 13% (n = 4) in the laparoscopic and 16% (n = 7) in the open group (p = 0.7). Conclusion  This study shows that, with a longer operative time, the laparoscopic approach, despite the learning curve, offers advantages regarding operative blood loss, postoperative analgesic requirement, time to regular diet, hospital stay, and overall cost compared with the open approach for minor liver resections. A part of this study was presented as a poster at the 2008 SAGES Meeting April 9-12, 2008 in Philadelphia, PA. An erratum to this article can be found at     

Comparison of oedema formation after CO2 and Nd-YAG laser therapy and cryosurgery

A comparison of oedema formation, as measured by leakage of the dye Evans blue from the circulation, was carried out in the laboratory rat employing standardized lesions on the anterior abdominal wall by various regimens of CO₂ laser, Nd-YAG laser and cryosurgery over a 4 h period. The CO₂ laser at high power produced significantly less oedema than any other modality (p<0.05) while the Nd-YAG laser at high power produced significantly more (p<0.05) than any other. Nd-YAG low power, cryosurgery in one of two freezes and the CO₂ laser at low power all produced a moderate degree of oedema (no significant difference). These findings have particular clinical relevance in sites where oedema may cause major functional or cosmetic problems as in the oro-facial region. The animals remained sedated over the period of observation so that any possible discomfort was eliminated.     

In vivo temperature measurement during transcatheter endomyocardial Nd-YAG laser irradiation in dogs

Intramural temperatures were monitored during catheter-directed endomyocardial non-contact laser irradiation by means of an array of thermocouples inserted epicardially. Via a novel electrode-laser catheter, a total of 30 Nd-YAG laser pulses, 1064 nm, 25 W/15 s, 20 W/30 s, 15 W/45 s,n = 10 each, were aimed at various endocardial sites in the ventricles of four dogs. Temperatures increased gradually after the onset of the laser pulses. Maximum values were measured in the central area of the irradiated spots: 100 ± 15 ‡C at 25 W, 78± 23 ‡C at 20 W and 80 ± 13 ‡C at 15 W. Application of 300 J of laser energy induced significantly higher temperatures at 25 W (p< 0.02) than at 20 or 15 W (20vs 15 W: p> 0.05). Initial temperature rise and lesion formation was accompanied by dwindling of local electrical potentials. There was no crater formation. Transcatheter non-contact Nd-YAG laser coagulation of healthy ventricular myocardium can be performed in a safe and controllable manner at power settings up to 20 W and laser energies up to 675 J.     

Comparative Study of the Early Postoperative Course and Complications in Patients Undergoing Billroth I and Billroth II Gastrectomy

p < 0.05). No patient in the BI group developed anastomic leakage. Two patients who underwent BII resection developed duodenal stump leakage (4.7%). Relaparotomy was indicated in five patients, two from the BI group (malignant cells in the resection margins) and three from the BII group (one due to duodenal stump leakage and two for bleeding). There was no postoperative mortality in the BI group. The postoperative mortality in the BII group was 7.1% ( p < 0.05). The average proximal gastric resection margins were significantly smaller in the BI group than in the BII group (3.65 ± 2.83 cm and 5.18 ± 2.57 cm, respectively; p < 0.05). The number of lymph nodes found in the resected specimen did not differ significantly between the two groups. Recurrent tumor at the gastric remnant developed in two patients in the BI group but not in the BII group. The results of our study revealed that the BI procedure is accompanied by significantly lower postoperative complication and mortality rates than the BII procedure in cases of gastric malignancy. BI resection performed for malignancy seems to achieve smaller proximal gastric resection margins, which may influence the recurrence rate.     

External beam,sapphire tip contact and interstitial Nd-YAG laser therapy at 1.064 μm on a transplanted adenocarcinoma in mice: A comparative study

This study was undertaken to compare three different techniques for treating transplanted tumours in mice with the Nd-YAG laser—no contact (external beam), interstitial, and sapphire tip contact therapy. The aspects studied were macroscopic and microscopic tumour necrosis and haemostasis. Forty C_57B1 male mice were transplanted with the adenocarcinoma AC₇₅₅ and divided into four groups—three experimental, one for each treatment technique and one control. On the 15th day after transplantation tumours were irradiated with an external, no contact beam (group I), interstitial therapy (group II) or contact therapy with a sapphire tip (group III), each with a light dose of 1200 J. Seventy-two hours later all animals (experimental and control) were killed, the tumours excised, weighed and the extent of necrosis measured macroscopically and microscopically and the blood vessels near the zone of necrosis examined. The best results were obtained in groups I and II (no contact and interstitial) compared with the controls (p<0.001 andp<0.01 for the tumour weight andp<0.01 andp<0.001 for the percentage of necrosis, respectively). Results from contact therapy were poor for each of the parameters chosen with no significant differences between the treated and control animals although marginally better coagulation was observed in this group. It is concluded that sapphire tip therapy has no advantages for tumour destruction but causes slightly better coagulation at the treatment point. Interstial therapy warrants further investigation.     

Tumor Necrosis Factor-α, Interleukin-1β and Nitric Oxide: Induction of Liver Megamitochondria in Prehepatic Portal Hypertensive Rats

Abstact It has been shown that portal hypertension in the rat causes microvesicular hepatocytic fatty infiltration. Formation of megamitochondria (MG) is one of the most prominent alterations in steatosis. Because nitric oxide (NO), tumor necrosis factor-α (TNFα), and interleukin-1β (IL-1β) impair mitochondrial function, these mediators have been studied in prehepatic portal hypertensive rats to verify their coexistence with MG and therefore with steatosis. Male Wistar rats were divided into two groups: a control group (n = 7) and a group with partial portal vein hgation (n = 19) at 6 weeks of evolution. TNFα and IL-1β were quantified in liver by enzyme-linked immunosorbent assay, and NO was measured in the portal vein, suprahepatic inferior vena cava, and infrahepatic inferior vena cava by the Griess reaction. In portal hypertensive rats, the-serum concentration of NO of hepatic origin increases (132.10 ± 34.72 vs. 52.44 ± 11.32 nmol/ml; p < 0.001), as do TNF-α (2.02 ± 0.20 vs. 1.12 ± 0.43 μmol/mg protein) and IL-1β (18.95 ± 2.59 vs. 5.48 ± 1.70 μmol/mg protein) (p = 0.005) in the liver. The most frequent hepatic histologic findings are the presence of MG (p < 0.001), steatosis, and hyperplasia. An increase in hepatic release of NO, TNFα and IL-Iβ with MG formation is produced in rats with portal hypertension. Therefore these proinflammatory mediators and this morphologic mitochondrial alteration could both be involved in the etiopathogenesis of steatosis.     

One-stage bilateral pulmonary resections for pulmonary metastases

Objective

We analyze the safety and efficacy of one-stage bilateral pulmonary resections for pulmonary metastases via a bilateral approach.

Methods

We retrospectively analyzed 154 cases with pathologically verified pulmonary metastases which underwent curative pulmonary resection. Intraoperative and perioperative variables were evaluated.

Results

One hundred and thirty cases underwent unilateral pulmonary metastasectomy (group U), and the other 24 cases with bilateral pulmonary metastases underwent one-stage bilateral pulmonary resections (group B). Operation time in group B was significantly longer than in group U (354 ± 132 vs. 203 ± 110 min; p < 0.001), but was not longer than double that in group U (407 ± 219 min; p = 0.540). Operative blood loss was not significantly greater in group B than group U (113 ± 158 vs. 76 ± 138 ml; p = 0.069). Neither duration of postoperative hospital stay nor incidence of postoperative complications differed between the two groups. Hospitalization costs in group B were significantly greater than in group U (257 ± 120 × 10⁴ vs. 168 ± 69.2 × 10⁴ yen; p < 0.001), but they were significantly less than double those in group U (336 ± 138 × 10⁴ yen; p < 0.001).

Conclusions

We consider one-stage bilateral pulmonary metastasectomy to be safe for bilateral pulmonary metastases. Moreover, it may offer an economic benefit by avoiding the expenses associated with a two-stage operation.     

Thoracic Epidural Anesthesia for Pain Relief and Postoperation Recovery with Modified Radical Mastectomy

p < 0.001) and decreased pethidine consumption (17.2 ± 7.0 vs. 76.3 ± 17.4 mg) (p < 0.001) were observed in the TEA group than in the GA group, respectively. A worse visual analog scale (VAS) pain score was observed in the GA group (5.7 ± 0.6) than in TEA patients (4.3 ± 0.4) (p < 0.01). The average bed rest time was significantly shorter in the TEA group (16.9 ± 0.9 hours) (p < 0.01) than in the GA group (27.1 ± 4.1 hours). Overall satisfaction scores were significantly higher in the TEA group (4.4 ± 0.1) (p < 0.01) than in the GA group (3.5 ± 0.2). Side effects were observed at a higher frequency in the GA group (16/32) (p < 0.0001) than in the TEA group (3/32). The frequency of pethidine injection for pain relief was significantly lower in the TEA group (8/32) (p < 0.0001) than in the GA group (24/32). The total hospital cost (NT 64,392 ± 3,523 vs. NT 53,806 ± 2,817) (p= 0.0342) and anesthesia cost (NT 7,968 ± 246 vs. NT 5,268 ± 262) (p < 0.0001) are also significantly lower in the TEA group than the GA group. In conclusion, TEA provided better postoperative pain relief and recovery and lower cost than GA for MRM surgery.     

Immediately recognizable benefits and drawbacks after laparoscopic colon resection for benign disease

Background: A prospective assessment of the impact of laparoscopic colon resection (LCR) was carried out in order to quantify immediately recognizable benefits and limitations of this approach. Methods: Elective LCR was attempted in 95 selected patients (mean age 64 years, range 39–81 years) presenting with benign disease of the colon. A completely intracorporeal approach was adopted. Results were compared with a control group of 90 patients who had previously undergone open colectomy (OC) by the same surgeons at the same institution. Results: There were no perioperative deaths. Intraoperative complications included difficult extraction of accidentally detached anvil (n= 1), air leak at colonoscopy (n= 2), and conversion to OC (n= 1). Operating time was significantly longer after LCR compared with OC (180 ± 10.3 vs 116 ± 97, p < 0.001). Passage of flatus (3.5 ± 1.2 days vs 4.4 ± 1.4, p < 0.5) and morbidity (4 vs 3, p= 0.48) were not significantly different in the two groups. Hospital stay was significantly shorter after LCR (5.2 ± 1.3 days vs 12.2 ± 1.9 days, p < 0.001). Theater and ward costs were, respectively, significantly increased ($ 2,829.6 ± 340 vs $ 1,422 ± 318, p < 0.001) and decreased ($ 2,600 ± 366 vs $ 6,022 ± 916, p < 0.001) in LCR patients compared with the OC group. There was no significant difference in total hospital costs ($ 10,929 ± 369 vs $ 9,944 ± 1,014). Conclusions: LCR does not appear to offer any immediately recognizable advantages. Received: 15 October 1996/Accepted: 13 December 1996     

Simultaneous resection for colorectal cancer and synchronous liver metastases

Purposes

The correct timing of hepatectomy in patients with synchronous colorectal liver metastases is unclear. The aim of this study was to assess the clinical value of simultaneous resection (SR) for patients with colorectal cancer and synchronous liver metastases.

Methods

Between January 2006 and December 2013, 158 patients underwent resection of primary colorectal cancer and liver metastases. Sixty-three patients possessed synchronous colorectal liver metastases. Of those with synchronous colorectal liver metastases, 41 patients (65 %) underwent SR, and 22 (35 %) underwent delayed resection (DR). The clinicopathologic and operative data and the surgical outcomes of the patients in the SR and DR groups were retrospectively analyzed.

Results

The type of primary/liver resection, liver resection time, total blood loss volume, R0 resection rate, and morbidity rate were similar between the two groups. The SR group was associated with a shorter total postoperative hospital stay (21 vs 32 days, p < 0.001). However, the overall survival rate was similar between the two groups (3-year survival, 65.6 % in the SR group versus 66.8 % in the DR group, p = 0.054).

Conclusion

Simultaneous resection of colorectal cancer and synchronous liver metastases is associated with a comparable morbidity rate and shorter hospital stay, even when following rectal resection and major hepatectomy.