RESUMEN
BACKGROUND: Little is know about the effects of different insufflation gases on peritoneal pH during laparoscopy. However, these changes may influence the intracellular signalling system, resulting in altered cell growth or adhesiveness. The aim of this study was to determine the effects of carbon dioxide (CO(2)), nitrous oxide (N(2)O), and helium (He) on parietal and visceral peritoneal pH. The effect of different intraabdominal pressures on parietal and visceral peritoneal pH was also examined. METHODS: We conducted both an ambient gas study and a pressure study. For the ambient gas study, 20 pigs were divided into the following four groups: (a) CO(2), (b) He, (c) N(2)O, and (d) abdominal wall lift (Lift) laparoscopy. Parietal and visceral peritoneal pH were measured at 15 min intervals for 180 min. For the pressure study, 15 pigs were divided into the following three groups: (a) CO(2), (b) He, (c) N(2)O laparoscopy. Baseline values were established for parietal and visceral peritoneal pH. Intraabdominal pressure was then increased stepwise at 1-mmHg intervals to 15 mmHg. After pressure was maintained for 15 min at each setting, parietal and visceral peritoneal pH were measured. RESULTS: Ambient gas environment was the major determinant of parietal peritoneal pH. Carbon dioxide caused parietal peritoneal acidosis. Helium, N(2)O, and Lift caused alkalotic parietal peritoneal pH. Intraabdominal pressure had a minor effect on parietal peritoneal pH. At higher intraabdominal pressure (12-15 vs 5-8 mmHg), CO(2) caused a slight decrease in parietal peritoneal pH, whereas N(2)O and He caused a slight increase in parietal peritoneal pH. Visceral peritoneal pH remained relatively unaffected during all studies. CONCLUSIONS: Parietal peritoneal pH during laparoscopy was highly dependent on the ambient gas environment. The effect of intraabdominal pressure on parietal peritoneal pH was of minor significance. Carbon dioxide caused a slight worsening of parietal peritoneal acidosis at higher intraabdominal pressure, whereas, N(2)O, He, and Lift did not cause parietal peritoneal acidosis.
Asunto(s)
Dióxido de Carbono/farmacología , Helio/farmacología , Laparoscopía , Óxido Nitroso/farmacología , Peritoneo/efectos de los fármacos , Peritoneo/metabolismo , Animales , Concentración de Iones de Hidrógeno , Periodo Intraoperatorio , Presión , PorcinosRESUMEN
BACKGROUND: Carbon dioxide (CO(2)) is the most common gas used for insufflation in laparoscopy, but its effects on peritoneal physiology are poorly understood. This study looks at the changes in peritoneal and bowel serosal pH during CO(2) pneumoperitoneum, and whether heating and humidification with or without bicarbonate alters the outcomes. METHODS: Twenty-one pigs divided into four groups as follows: (1) standard (STD) laparoscopy (n = 5); (2) heated and humidified (HH) laparoscopy (n = 6); (3) heated and humidified with bicarbonate (HHBI) laparoscopy (n = 5); and (4) laparotomy (n = 5). Peritoneal pH, bowel serosal pH, and arterial blood gas (ABG) were obtained at 15-min intervals for 3 h. RESULTS: Severe peritoneal acidosis (pH range 6.59-6.74) was observed in all laparoscopy groups, and this was unaltered by heating and humidification or the addition of bicarbonate. Bowel serosal acidosis was observed in all laparoscopy groups with onset of pneumoperitoneum, but it recovered after 45 minutes. No significant changes in peritoneal or bowel serosal pH were observed in the laparotomy group. CONCLUSION: CO(2) pneumoperitoneum resulted in severe peritoneal acidosis that was unaltered by heating and humidification with or without bicarbonate. Alteration in peritoneal pH may conceivably be responsible for providing an environment favorable for tumor-cell implantation during laparoscopy.
Asunto(s)
Acidosis/inducido químicamente , Dióxido de Carbono/efectos adversos , Enfermedades Peritoneales/inducido químicamente , Neumoperitoneo Artificial/métodos , Animales , Bicarbonatos/uso terapéutico , Modelos Animales de Enfermedad , Calor/uso terapéutico , Humedad , Índice de Severidad de la Enfermedad , Porcinos , Insuficiencia del TratamientoAsunto(s)
Endoscopía , Robótica , Endoscopía/economía , Endoscopía/métodos , Humanos , Robótica/economía , Robótica/instrumentaciónRESUMEN
BACKGROUND: Gastric outlet obstruction in patients with pancreatic cancer has a grim prognosis. Open surgical bypass is associated with high morbidity, whereas endoscopic duodenal stenting appears to provide better palliation. METHODS: We reviewed the medical records of patients with gastric outlet obstruction secondary to pancreatic carcinoma who were admitted to our clinic between 1 October 1988, and 30 September 1998. The data included stage of disease, American Society of Anesthesiologists (ASA) class, surgical interventions, complications, and survival. RESULTS: A total of 250 patients with pancreatic cancer were identified. Twenty-five of them (10%) had gastric outlet obstruction. Of these 25, 17 were treated with gastrojejunostomy, six had duodenal stenting (Wallstent), and two were resectable. There was no significant difference between the gastrojejunostomy group and the duodenal stenting group in ASA class or stage of disease. For the gastrojejunostomy group, median survival was 64 days (range, 15-167) and postoperative stay in hospital was 15 days (range, 8-39). For the duodenal stenting group, median survival was 110.5 days (range, 42-212) and postoperative stay was 4 days (range, 2-6). Ten patients (58.8%) in the gastrojejunostomy group had delayed gastric emptying. All of the patients in the duodenal stenting group were able to tolerate a soft diet the day after stent placement. Thirty-day mortality in the gastrojejunostomy group was 17.64%; in the duodenal stenting group, it was 0. CONCLUSION: In pancreatic carcinoma patients with gastric outlet obstruction, duodenal stenting results in an earlier discharge from hospital and possibly improved survival.
Asunto(s)
Obstrucción de la Salida Gástrica/etiología , Obstrucción de la Salida Gástrica/cirugía , Gastroscopía/métodos , Cuidados Paliativos/métodos , Neoplasias Pancreáticas/complicaciones , Anciano , Duodeno/cirugía , Femenino , Obstrucción de la Salida Gástrica/mortalidad , Humanos , Masculino , Persona de Mediana Edad , Neoplasias Pancreáticas/mortalidad , Stents , Tasa de SupervivenciaRESUMEN
The merit of intraoperative ultrasonography in abdominal surgery has been recognized for several decades and has been well documented in the literature. With the proliferation of laparoscopic abdominal surgery, laparoscopic ultrasonographic technology rapidly developed and studies have confirmed its value in staging intra-abdominal malignancy. The combination of diagnostic laparoscopy and laparoscopic ultrasonography has been shown to be consistently superior to other preoperative imaging modalities in the staging of abdominal malignancy. Consequently there has been an improvement in the management of patients with abdominal malignancy, demonstrated by reductions in nontherapeutic laparotomies, improved resectability rates, and optimization of palliation.
Asunto(s)
Neoplasias Abdominales/diagnóstico por imagen , Neoplasias Abdominales/cirugía , Neoplasias del Sistema Digestivo/diagnóstico por imagen , Neoplasias del Sistema Digestivo/cirugía , Humanos , Laparoscopía , Estadificación de Neoplasias , Ultrasonografía/métodosRESUMEN
BACKGROUND: Benign gastric tumors and tumors of low-grade malignancy can be safely removed laparoscopically. METHODS: Seven patients were considered candidates for laparoscopic resection of gastric tumors. Inclusion criteria included small tumor size (less than 6 cm), exophytic or endophytic tumor morphology, and benign characteristics. Indications for surgical intervention included bleeding, weight loss, and need for tissue diagnosis. Patients ranged in age from 38 to 70. There were five female and two male patients. All patients underwent preoperative upper GI endoscopy. The procedures were performed using a four- or five-port technique. An Endo-GIA (US Surgical Company, Norwalk, Connecticut) was used to amputate those tumors located on the serosal surface of the stomach. Tumors on the mucosal surface were exposed via a gastrotomy, then likewise amputated using an Endo-GIA. The gastrotomy closure was then either hand sewn or stapled. Operating time ranged from 95 to 225 min. RESULTS: Final pathologic diagnoses included lipoma, lymphoma, leiomyoma, and leiomyosarcoma. There was a 28% conversion rate. There were no complications. Length of postoperative stay ranged from 4 to 7 days. There have been no tumor recurrences in 6-38-month follow-up. CONCLUSIONS: Minimally invasive management of benign and low-grade gastric tumors can be performed safely with excellent short- and long-term results.
Asunto(s)
Gastrectomía/métodos , Procedimientos Quirúrgicos Mínimamente Invasivos , Neoplasias Gástricas/cirugía , Adulto , Anciano , Femenino , Humanos , Leiomioma/cirugía , Leiomiosarcoma/cirugía , Lipoma/cirugía , Linfoma/cirugía , Masculino , Persona de Mediana Edad , Neoplasias Gástricas/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Resultado del TratamientoRESUMEN
BACKGROUND AND STUDY AIMS: The aim of the present study was to determine the safety, efficacy, and feasibility of a one-stage retrograde approach to Nd:YAG laser palliation of esophageal carcinoma carried out under general anesthesia. PATIENTS AND METHODS: Endoscopic Nd:YAG laser therapy was used on 150 occasions in 62 consecutive patients with advanced malignant obstruction of the esophagus. All procedures were carried out under general anesthesia. The lesion was first dilated using a Savary-Gilliard dilator or balloon technique, and the endoscope was then passed beyond the lesion. Laser energy was applied to the lesion in a circumferential manner as the scope was withdrawn along the length of the lesion, until an adequate lumen was established. RESULTS: Ninety-three percent of the patients had symptomatic improvement, defined as reduction in the subjective dysphagia grade, and only 14% of the patients required repeat procedures within 30 days. Fifty percent of the patients experienced effective palliation with only one procedure over the entire course of their illness. In patients with recurrent dysphagia, the mean time between procedures was 100 days. Seventy-six percent of the patients were discharged on the day following the procedure. Complications included the development of pneumomediastinum or subcutaneous emphysema in five cases, and esophageal perforation in two cases. All cases of pneumomediastinum or subcutaneous emphysema or perforation were managed by conservative therapy. Hemorrhage requiring transfusion occurred in two cases. There were three apparently procedure-related deaths occurring within 30 days of the initial procedure. CONCLUSIONS: Effective palliation of obstructing esophageal carcinoma can be achieved in one session using a one-stage retrograde approach with the Nd:YAG laser under general anesthesia. When compared to other palliative modalities, this method produces a longer dysphagia-free interval, and patients with a terminal illness are therefore able to spend more time out of hospital.
Asunto(s)
Carcinoma/cirugía , Endoscopía , Neoplasias Esofágicas/cirugía , Terapia por Láser , Cuidados Paliativos , Adulto , Anciano , Anciano de 80 o más Años , Silicatos de Aluminio , Anestesia General , Transfusión Sanguínea , Cateterismo , Trastornos de Deglución/cirugía , Endoscopios , Endoscopía/efectos adversos , Endoscopía/métodos , Perforación del Esófago/etiología , Estenosis Esofágica/cirugía , Estudios de Factibilidad , Femenino , Humanos , Terapia por Láser/efectos adversos , Terapia por Láser/instrumentación , Terapia por Láser/métodos , Masculino , Enfisema Mediastínico/etiología , Persona de Mediana Edad , Neodimio , Hemorragia Posoperatoria/etiología , Hemorragia Posoperatoria/terapia , Reoperación , Seguridad , Enfisema Subcutáneo/etiología , Tasa de Supervivencia , ItrioRESUMEN
Urological laparoscopy has gained increasing acceptance recently. Alterations in renal water and electrolyte homeostasis by carbon dioxide peritoneal insufflation, retroperitoneal insufflation and abdominal wall lifting were measured in 30 well-hydrated pigs over a 2-h period. Oliguria was observed after gaseous insufflation but not alter lifting the abdominal wall. Return to normal urinary output was observed at 30 min after release of pneumoretroperitoneum, and 60 min after pneumoperitoneum. Creatinine clearance declined, while the clearance rates of potassium, sodium and urea remained unchanged during peritoneal and retroperitoneal insufflation. An elevated serum aldosterone concentration was found which may mediate the increased urinary excretion of potassium and decreased urinary excretion of sodium found during peritoneal insufflation. Renal function remained stable, despite an elevation of serum creatine kinase being elicited after lifting the abdominal wall. In conclusion, significant changes in water and electrolyte homeostasis occurred gaseous, not gasless, laparoscopy in pigs.
Asunto(s)
Diuresis , Electrólitos/orina , Laparoscopía/métodos , Animales , Creatina Quinasa/sangre , Femenino , Gases , Homeostasis , Insuflación , Periodo Intraoperatorio , Riñón/metabolismo , PorcinosRESUMEN
Laser Doppler flowmetry (LDF) is a sensitive method for the measurement of microvascular blood flow in tissue. The method has been found useful for estimating skin, liver, or gastrointestinal blood flow. Whether it can be applied laparoscopically and whether it is able to measure the intraparenchymal blood flow of an intraabdominal organ is still unknown. In a pilot study, 6 pigs received a laparotomy for placement of a 19-gauge LDF needle probe into the renal parenchyma. Three different locations of the lower pole kidney were chosen for the blood flow measurement. The reliability of using the instrument to measure the renal tissue blood flow was assessed by comparison of the results of renal arterial blood flow obtained from a well-established methodology--ultrasonic Doppler flowmetry. Recordings were taken following (a) intravenous administration of 0.005 mg/kg norepinephrine, (b) manual compression of the suprarenal aorta, and (c) intravenous injection of a lethal dose of phenobarbital (50 mg/kg). Measurements of LDF were possible in all kidney units. The renal tissue perfusion detected by LDF correlated excellently with the renal arterial blood flow under different renal perfusion pressures. The feasibility of using LDF probe to measure the renal tissue perfusion in a laparoscopic model was then assessed in 15 pigs. Under pneumoperitoneum, the right kidneys were approached transperitoneally with the animal in the decubitus position. A total of three trocars were used. The peritoneum and Gerota's fascia were incised and the LDF needle probe was manipulated and inserted by an endoforceps into the renal tissue via a 5-mm trocar. The insertion of the LDF needle probe was technically feasible in all 15 kidney units, and the depth of insertion could be adjusted under direct vision. Baseline values for the renal cortical and renal medullary blood flow were 50.1 +/- 17.7 and 8.8 +/- 3.3 ml/min/100 g tissue, respectively. Spatial variations of the LDF measurements averaged 6%, and temporal variations over 15 min averaged 5%. Four additional hemodynamic parameters were simultaneously recorded, including left carotid artery blood flow, aortic blood pressure, inferior vena caval pressure, and intraabdominal pressure. It appears that systemic and renal hemodynamic parameters can be monitored reliably and continuously in the porcine model. This method allows further information concerning hemodynamic changes and safety of laparoscopy to be obtained.
Asunto(s)
Laparoscopía , Circulación Renal , Animales , Modelos Animales de Enfermedad , Hemodinámica , Humanos , Periodo Intraoperatorio , Flujometría por Láser-Doppler , Modelos Biológicos , Monitoreo Fisiológico , Proyectos Piloto , Sensibilidad y Especificidad , PorcinosRESUMEN
BACKGROUND: The use of therapeutic laparoscopy has become widespread recently. It is important to assess the effects of gaseous and gasless laparoscopy on systemic and renal hemodynamics. STUDY DESIGN: A prospective controlled animal study was performed on 40 well-hydrated pigs. Systemic and renal hemodynamics were monitored during peritoneal insufflation, retroperitoneal insufflation, and abdominal wall lifting for a period of two hours. A laser Doppler flow meter was applied laparoscopically to measure the renal cortical tissue perfusion. RESULTS: Peritoneal insufflation of carbon dioxide to a pressure of 15 mm Hg elicited transient elevations of the aortic pressure and carotid arterial blood flow. Unilateral pneumoretroperitoneum caused a smaller change on systemic hemodynamics. Pneumoperitoneum and pneumoretroperitoneum caused oliguria. Superficial renal cortical blood flow reduction decreased by an average of 60 percent in the compressed kidney, and blood flow returned to the pre-insufflation level after the pressure was released. A gradual decrease of tissue perfusion in the contralateral kidney and a concomitant gradual increase of the intra-abdominal pressure were observed when pneumo-retroperitoneum was maintained for two hours. No significant changes in urinary output and in systemic and renal hemodynamics were found when the abdominal wall was lifted up with a force equivalent to 15 mm Hg. CONCLUSIONS: Significant systemic and renal hemodynamic changes were elicited in gaseous but not in gasless laparoscopy, which may explain the decreased urinary output observed during gaseous laparoscopy. Pneumoperitoneum caused greater systemic and renal hemodynamic alterations than pneumoretroperitoneum; however, the effects were transient and reversible after a period of two hours.
Asunto(s)
Hemodinámica , Riñón/fisiología , Laparoscopía , Neumoperitoneo Artificial , Animales , Presión Sanguínea , Arterias Carótidas/fisiología , Laparoscopía/métodos , Estudios Prospectivos , Flujo Sanguíneo Regional , PorcinosRESUMEN
OBJECTIVE: To investigate the effect of apneumic retraction on intracranial pressure (ICP) using a live porcine model. DESIGN: Five 25- to 30-kg pigs had a fiber-optic ICP bolt inserted under general endotracheal anesthesia and were monitored for ICP, mean arterial pressure, arterial blood gas measurements, and intra-abdominal pressure before, during, and after pneumoperitoneum, with each period 30 minutes long. These series of measurements were repeated after artificially raising ICP with an epidural balloon to create a head-injured model. The mean (+/- SE) ICP in the noninjured model at baseline was 13.46 +/- 1.01 mm Hg; during pneumoperitoneum, 18.72 +/- 1.50 mm Hg (P = .0001). Similarly, in the head-injured model, ICP was raised artificially to a new baseline of 22 +/- 1.75 mm Hg with an epidural balloon, and pneumoperitoneum increased ICP to 27.40 +/- 0.93 mm Hg (P = .0001). Pneumoperitoneum was then released, and an apneumic retractor was inserted while maintaining the inflated epidural balloon. MAIN OUTCOME MEASURE: Changes in ICP. RESULTS: Applying anterior wall retraction equivalent to 20 mm Hg was not associated with changes in ICP. These observations were independent of any changes in arterial PCO2 or arterial pH. Following the release of pneumoperitoneum, abdominal wall retraction, and epidural balloon, all measurements reverted to baseline. CONCLUSION: Pneumoperitoneum adversely affects ICP, while apneumic retraction may not affect animals with raised ICP. These findings suggest that pneumoperitoneum should be used with caution in patients with raised ICP, and apneumic retraction may be a safer alternative for laparoscopic evaluation in this population.
Asunto(s)
Traumatismos Craneocerebrales , Presión Intracraneal , Laparoscopios , Músculos Abdominales , Animales , Cateterismo , Diseño de Equipo , Laparoscopía/efectos adversos , Neumoperitoneo Artificial , Presión , PorcinosRESUMEN
This study was set up to compare three-dimensional imaging of a new three-dimensional laparoscope with two-dimensional imaging in the inanimate and clinical settings. In the clinical setting the laparoscope was used in a total of 50 different laparoscopic operations. It provided excellent depth perception, definition, and resolution. The relationships of structures were more easily defined, and instrument manipulation was easier, doing away with the need for "touch and feel" to determine instrument position. Three-D imaging made cannulation of the cystic duct for cholangiography or with a flexible choledochoscope easier. In the inanimate setting basic simple tasks took the same time in 2-D as in 3-D, whereas a more complicated procedure of passing a needle and suture through a series of hoops was 25% faster when performed in 3-D compared to 2-D. Three-D imaging may reduce operative time for laparoscopic procedures, particularly the more complicated operations.
Asunto(s)
Procesamiento de Imagen Asistido por Computador , Laparoscopios , Procesamiento de Señales Asistido por Computador , Colangiografía , Colecistectomía Laparoscópica , Hernia Inguinal/cirugía , Humanos , Cuidados Intraoperatorios/instrumentación , Modelos Estructurales , Grabación en VideoRESUMEN
Electrosurgical energy may be utilized as an adjunct to mechanical force for insertion of laparoscopic trocars. The advantage of this approach may be better operator control of insertion, with less risk of intraperitoneal and retroperitoneal injury. To assess the safety and efficacy of electrosurgical trocars, we compared them to mechanical trocars in clinical and animal trials. During 100 trocar introductions in 25 laparoscopic cholecystectomies, insertion force was measured. In contrast to mechanical trocars, which required progressively more force to insert as size increased, electrosurgical trocars required the same low insertion force regardless of size. No wound complications occurred. In animal experiments, wound healing (measured histologically and by bursting strength) was normal and equivalent for mechanical and electrosurgical insertions. We conclude that electrosurgical trocars require less force for insertion and do not impair wound healing. Electrosurgical trocars may thus offer important safety advantages over mechanical trocars.
Asunto(s)
Electrocirugia/instrumentación , Laparoscopios , Músculos Abdominales/cirugía , Animales , Colecistectomía Laparoscópica/efectos adversos , Colecistectomía Laparoscópica/instrumentación , Electrodos , Electrocirugia/efectos adversos , Diseño de Equipo , Seguridad de Equipos , Estudios de Evaluación como Asunto , Humanos , Complicaciones Intraoperatorias/prevención & control , Laparoscopía/efectos adversos , Ensayo de Materiales , Peritoneo/cirugía , Punciones/instrumentación , Conejos , Acero Inoxidable , Estrés Mecánico , Cicatrización de HeridasRESUMEN
There are numerous reports in the literature concerning the use of laparoscopy for evaluation of abdominal trauma victims. The safety of laparoscopic evaluation in trauma patients with potentially severe intracranial injuries has not yet been analyzed. This study investigates the effect of pneumoperitoneum on intracranial pressure (ICP) and cerebral perfusion pressure. Five 30-kg pigs were monitored for ICP, mean arterial pressure (MAP), arterial blood gases (ABGs), and intra-abdominal pressure (IAP) for 30 minutes before, during, and after pneumoperitoneum. These series of measurements were repeated after artificially elevating the ICP with an epidural balloon. The mean ICP at baseline was 13.46 +/- 1.01 mm Hg. The mean ICP during pneumoperitoneum was 18.72 +/- 1.50 mm Hg (p = 0.0001). The ICP increased to 27.40 +/- 0.93 mm Hg (p = 0.0001) after the ICP was raised artificially to a new baseline of 22 +/- 1.75 mm Hg with the epidural balloon. These increases were independent of changes in arterial PCO2 or arterial pH. Pneumoperitoneum during laparoscopy may increase ICP and must be used cautiously in evaluating patients with severe head injuries.