Abnormal heart rate characteristics before clinical diagnosis of necrotizing enterocolitis.

OBJECTIVE: Earlier diagnosis and treatment of necrotizing enterocolitis (NEC) in preterm infants, before clinical deterioration, might improve outcomes. A monitor that measures abnormal heart rate characteristics (HRC) of decreased variability and transient decelerations was developed as an early warning system for sepsis. As NEC shares pathophysiologic features with sepsis, we tested the hypothesis that abnormal HRC occur before clinical diagnosis of NEC. STUDY DESIGN: Retrospective review of Bells stage II to III NEC cases among infants <34 weeks gestation enrolled in a prospective randomized clinical trial of HRC monitoring at three neonatal intensive care units. RESULT: Of 97 infants with NEC and HRC data, 33 underwent surgical intervention within 1 week of diagnosis. The baseline HRC index from 1 to 3 days before diagnosis was higher in patients who developed surgical vs medical NEC (2.06±1.98 vs 1.22±1.10, P=0.009). The HRC index increased significantly 16 h before the clinical diagnosis of surgical NEC and 6 h before medical NEC. At the time of clinical diagnosis, the HRC index was higher in patients with surgical vs medical NEC (3.3±2.2 vs 1.9±1.7, P<0.001). CONCLUSION: Abnormal HRC occur before clinical diagnosis of NEC, suggesting that continuous HRC monitoring may facilitate earlier detection and treatment.

Discharge outcomes of extremely low birth weight infants with spontaneous intestinal perforations.

OBJECTIVE: To examine discharge outcomes of extremely low birth weight infants (ELBW) with spontaneous intestinal perforation (SIP). STUDY DESIGN: A single-center retrospective cohort study of all ELBW infants admitted to the University of Virginia neonatal intensive care unit between July 1996 and June 2004. RESULTS: We found 35 patients with SIP (incidence 8.4%). The median gestational age was 25 weeks, median birth weight was 722 g, and 71% of the infants were male. Most infants (n=28) with SIP were diagnosed secondary to pneumoperitoneum; however, one-third (7) of infants<25 weeks had occult presentations without pneumoperitoneum. When controlled for gestational age, gender, multiple gestation, indomethacin, and glucocorticoid exposure, infants with SIP have a higher risk of PVL and death than infants without perforation. SUMMARY: Periventricular leukomalacia and death are significantly associated with SIP in ELBW after adjusting for gestational age, multiple gestation, indomethacin, and glucocorticoid exposure.

Follow-up abdominal computed tomography after splenic trauma in children may not be necessary.

Nonoperative management of splenic injuries in children is well accepted. However, the need for follow-up abdominal CT to document splenic healing has not been well studied. We retrospectively reviewed initial and follow-up abdominal CT examinations of pediatric patients admitted to our institution with documented splenic trauma who were managed nonoperatively. Eighty-four patients were admitted to our pediatric surgical service with splenic injury documented by CT from 1994 through 1998. The standard approach for splenic injury was bedrest for 5 to 21 days and limited activity for up to 90 days at the discretion of the attending surgeon. Thirty-five of the 84 had follow-up CTs during outpatient follow-up to evaluate and document splenic healing by CT criteria. The initial and follow-up studies were randomized and read blindly by pediatric radiologists using a modified American Association for the Surgery of Trauma grading system (I-V). The age range of the patients was 6 months to 17 years (mean +/- SE; 11 +/- 1 years). Nineteen (54%) were male and 16 (46%) were female. Causes of splenic trauma included motor vehicle accident (22), fall (seven), assault (four), pedestrian versus vehicle (one), and sports injury (one). Eight children (23%) had grade II injuries, 14 (40%) had grade III injuries, and 13 children (37%) had grade IV injuries on initial CT scan. Seven (88%) of the grade II splenic injuries were healed by 64 +/- 11 days. The remaining grade II injury had healed by 210 days. Thirteen (93%) of the grade III splenic injuries were healed by 76 +/- 7 days. The remaining grade III injury was healed by 140 days. Spleens in 10 (77%) of the 13 patients with grade IV injuries were healed by 81 +/- 8 days. Of the three remaining grade IV injuries two were healed by 173 +/- 14 days. The remaining patient's spleen was radiologically considered to have a grade III defect 91 days from the time of injury, and no further CTs were obtained. Of the 34 patients who underwent follow-up CT imaging until splenic healing was demonstrated the mean time to complete healing was 87 +/- 8 days postinjury (range 11-217 days). These data suggest that routine follow-up abdominal CTs may not be necessary to allow children to resume their normal activities after an appropriate time of restricted activity.

Effects of carotid artery repair following neonatal extracorporeal membrane oxygenation.

Between 1 June 1991 and 30 June 1996, 62 neonates were placed on extracorporeal membrane oxygenation (ECMO). In 61 the right carotid artery was cannulated. At the time of decannulation, a decision was made regarding carotid artery repair (CAR) based on the condition of the vessel. Thirty-two patients underwent end-to-end CAR and 29 had artery ligation. There was no difference between groups in gestational age or birth weight, but the ligation group contained 11 patients with congenital diaphragmatic hernia, compared to 2 in the repair group. The time on ECMO was 148 h for the repair group and 297 h in the ligation group. Follow-up contrast-enhanced magnetic resonance imaging (MRI) studies and ultrasound (US) demonstrated 2 occluded vessels in the repair group (7%); 3 vessels appeared stenotic on MRI. Follow-up neurologic examination was normal or near-normal in 17 of 19 repair infants and 9 of 16 ligation patients. Two repair infants had slight delays in development, while 3 ligation patients had significant delays. Follow-up US showed 3 grade I changes in the repair group with 1 hydrocephalus. There was 1 grade I and 1 grade III change in the ligation group. Follow-up MRI showed 6 minimal changes in the repair group and 9 in the ligation group. CAR does not adversely affect neurologic outcome after neonatal ECMO. The early patency rate was 93%, although 12% of the vessels appeared stenotic. Long-term follow-up confirmed persistent patency. CAR, if technically feasible, should be encouraged following neonatal ECMO therapy.

The role of peritoneal drainage for intestinal perforation in infants with and without necrotizing enterocolitis.

BACKGROUND/PURPOSE: This report reviews our experience using peritoneal drainage (PD) as initial therapy for intestinal perforation in premature infants with and without necrotizing enterocolitis (NEC). METHODS: A chart review was conducted of 18 consecutive premature infants who underwent PD for intestinal perforation from 1995 to 1998. Infants were divided into two groups. Group 1 consisted of eight infants who had intestinal perforation without evidence of NEC. Group 2 consisted of 10 infants who had perforation associated with evidence of NEC. A cohort of 10 infants with intestinal perforation treated with primary laparotomy between 1990 and 1995 was identified by chart review for historical control. RESULTS: All infants improved immediately after PD. In group 1, all survived. Seven (88%) recovered systemically after PD. Of these, five (63%) never required laparotomy. Two (25%) required delayed laparotomy. One infant (12%) failed to continue to improve 48 hours after PD and underwent urgent laparotomy and recovered. In group 2, eight (80%) infants survived. Six (60%) recovered from NEC after PD, but five required delayed laparotomy for obstruction or persistent drainage. Four infants (40%) failed to progress from their initial improvement after PD. Three underwent laparotomy; two recovered and one had total intestinal necrosis and died. The fourth infant died without exploration and total intestinal necrosis was discovered during autopsy. Thus, seven of eight survivors (88%) in group 2 required laparotomy at some point in their course. CONCLUSIONS: In premature infants with intestinal perforation, PD allows acute improvement and usually systemic recovery. In infants without evidence of NEC, PD may afford definitive treatment. In contrast, infants with evidence of NEC will likely require laparotomy, but initial PD may allow systemic stabilization and recovery of much of the involved intestine before laparotomy.

Successful management of stage 4S neuroblastoma and severe hepatomegaly using absorbable mesh in an infant.

This report describes the use of an absorbable mesh in an infant with stage 4S neuroblastoma who required decompressive laparotomy. At the time of laparotomy, a SILASTIC silo was placed. After 12 days, the liver had not reduced in size despite chemotherapy and radiation therapy. Because of concern for infection, the silo was removed, and an absorbable polygalactin (Vicryl) mesh was placed. Wet-to-dry dressings were used to manage the mesh. A granulation base developed that provided a physiological closure of the abdominal cavity. Forty-two days after placement of the absorbable mesh, the liver had reduced to a size that permitted mobilization of skin flaps for a surgical abdominal closure. The liver continued to reduce in size, allowing the fascial edges to draw together. The patient is now 2 years old with no signs of residual tumor or ventral hernia.

Capillaries and arterioles are electrically coupled in hamster cheek pouch.

In this report we demonstrate electrical communication in the microcirculation between arterioles and capillary networks in situ. Microvessel networks in the hamster cheek pouch, which included capillaries and their feeding arterioles, were labeled with the voltage-sensitive dye di-8-ANEPPS by intraluminal perfusion through a micropipette. Pulses of 140 mM potassium solution were applied by pressure ejection from micropipettes positioned on arterioles several hundred micrometers upstream from capillaries. Potassium caused membrane potential changes of 3-11 mV in capillary segments up to 1,200 micrometers distal to the stimulation site, with time delays of <1 s. Capillary membrane potential changes were biphasic, with initial depolarizations followed by hyperpolarizations. The size of the response decreased exponentially with the distance between the arteriole and capillary, with a 1/e distance of 590 micrometers. The time to peak depolarization of both arteriolar and capillary segments was similar. The time to peak response was significantly faster than that for responses from direct stimulation of capillaries. Capillary responses were also obtained when blood flow was either blocked or directed toward sites of stimulation. Acetylcholine (10(-4) M) and phenylephrine (10(-5) M) applied to the arterioles by iontophoresis produced monophasic hyperpolarizing and depolarizing responses, respectively, in capillaries with <1-s delay between stimulus and onset of the membrane potential change. These results provide evidence in situ of a pathway for electrical communication between arteriolar and capillary levels of the microcirculation.

Capillaries demonstrate changes in membrane potential in response to pharmacological stimuli.

It has been proposed that capillaries can detect changes in tissue metabolites and generate signals that are communicated upstream to resistance vessels. The mechanism for this communication may involve changes in capillary endothelial cell membrane potentials which are then conducted to upstream arterioles. We have tested the capacity of capillary endothelial cells in vivo to respond to pharmacological stimuli. In a hamster cheek pouch preparation, capillary endothelial cells were labeled with the voltage-sensitive dye di-8-ANEPPS. Fluorescence from capillary segments (75-150 microns long) was excited at 475 nm and recorded at 560 and 620 nm with a dual-wavelength photomultiplier system. KCl was applied using pressure injection, and acetylcholine (ACh) and phenylephrine (PE) were applied iontophoretically to these capillaries. Changes in the ratio of the fluorescence emission at two emission wavelengths were used to estimate changes in the capillary endothelial membrane potential. Application of KCl resulted in depolarization, whereas application of the vehicle did not. Application of ACh and PE resulted in hyperpolarization and depolarization, respectively. The capillary responses could be blocked by including a receptor antagonist (atropine or prazosin, respectively) in the superfusate. We conclude that the capillary membrane potential is capable of responding to pharmacological stimuli. We hypothesize that capillaries can respond to changes in the milieu of surrounding tissue via changes in endothelial membrane potential.

Neurological outcome is diminished in survivors of congenital diaphragmatic hernia requiring extracorporeal membrane oxygenation.

In a series of 61 infants who had congenital diaphragmatic hernia (CDH) treated at our center from 1978 through 1996, 37 of 59 (61%) survived the perioperative period with two infants lost to follow-up. Nine (47%) of 19 infants survived before the introduction of extracorporeal membrane oxygenation (ECMO) into our region in 1986. Since 1986, 28 (70%) of 40 infants survived. Eighteen infants required ECMO, and 12 (75%) survived. A chart review was performed to determine whether infants surviving CDH are suffering from delays in neurological development, and, if so, whether this is attributable to ECMO. Of 12 ECMO survivors, 8 (67%) exhibited functional or anatomic evidence for neurological delay. Of 21 non-ECMO survivors, where adequate follow-up was available to make an assessment of neurological development, five (24%) exhibited evidence for delay. This difference was significant (P < .05, Fisher's Exact test). Of these five infants, three were premature, and one had DiGeorge syndrome. More ECMO survivors required diaphragmatic (67%) and abdominal (67%) patches at the time of diaphragmatic repair than non-ECMO survivors (4% and 12%, respectively; P < .05, Fisher's Exact test). In addition, more ECMO survivors required gastrostomy tube placement for feeding (50%) than non-ECMO survivors (16%; P < .05, Fisher's Exact test). A greater need for Nissen fundoplication in ECMO survivors (42%) than in non-ECMO survivors (12%) approached significance (P = .05, Fisher's Exact test). There were trends toward higher 1 and 5 minute APGAR scores and initial and best preoperative P(O2) in the non-ECMO survivors. A comparison between ECMO survivors who exhibited evidence of neurological delay with those who did not showed no differences in duration of ECMO, incidence of intracranial complications during ECMO, need for gastrostomy tube feeding or Nissen fundoplication, or incidence of carotid artery repair between the two groups. Infants surviving CDH who require ECMO have a greater incidence of neurological delay than those who do not. This is likely because of severity of the presenting illness as reflected by a greater need for diaphragmatic and abdominal patches during diaphragmatic repair, the need for Nissen fundoplication and gastrostomy tube feeding, and a trend toward poor APGAR scores and best preoperative P(O2) levels in these patients. However, there may be characteristics of ECMO, as yet unidentified, that may contribute to this outcome.

A test of the role of flow-dependent dilation in arteriolar responses to occlusion.

At an arteriolar bifurcation, occlusion of one of the branch arterioles has been reported to result in an increase in flow, shear stress, and vasodilation in the opposite unoccluded branch. This dilator response in the unoccluded branch, often referred to as the "parallel occlusion response," has been cited as evidence that flow-dependent dilation is a primary regulator of arteriolar diameter in the microcirculation. It has not been previously noted that, during this maneuver, flow through the feed arteriole would be expected to decrease and logically should cause that vessel to constrict. We tested this prediction in vivo by measuring red blood cell (RBC) velocity and diameter changes in response to arteriolar occlusion in the microcirculatory beds of three preparations: the hamster cheek pouch, the hamster cremaster, and the rat cremaster. In all preparations, a vasodilation was observed in the feed arteriole, despite a decrease in both flow and calculated wall shear stress through this vessel. Unexpectedly, we found that dilation occurred in the unoccluded branch arterioles even in those cases in which RBC velocity and shear stress did not increase in the unoccluded branch arterioles. All values returned to the baseline level after the removal of occlusion. The magnitude of the dilation of the feed and branch arterioles varied between species and tissues, but feed and branch arterioles within a given preparation always responded in a similar way to each other. We conclude from our experiments that mechanisms other than flow-dependent dilation are involved in the vasodilation observed in the microcirculation during occlusion of an arteriolar branch.

Ratiometric measurement of endothelial depolarization in arterioles with a potential-sensitive dye.

A fluorescence ratio technique based on the voltage-sensitive dye 1-(3-sulfonatopropyl)-8-[beta-[2-di-n-butylamino)-6-naphythyl++ +]vinyl] pyridinium betaine (di-8-ANEPPS)has been developed for recording membrane potential changes during vascular responses of arterioles. Perfusion of hamster cheek pouch arterioles with the dye labeled the endothelial cell layer. voltage responses from the endothelium of intact arterioles were determined by analysis of voltage-induced shifts in fluorescence emission wavelengths from dye spectra imaged from the vessel wall. Membrane depolarization caused the dye spectrum to shift toward blue wavelengths, with maximal fluorescence changes near 560 and 620 nm. In isolated nonperfused arterioles, comparison of continuous dual-wavelength recordings with simultaneous microelectrode recordings showed that the ratio of fluorescence intensities (fluorescence at 620 nm to fluorescence at 560 nm) accurately followed changes in membrane potential (6-21 mV) during vasoconstriction. The dye response was linear with respect to potential changes from -56 to -6 mV, with a voltage sensitivity of 9.7% change in the ratio per 100 mV. Membrane potential responses from in vitro and in vivo arterioles after potassium stimulation consisted of rapid ( < 0.5 -s) depolarization followed by slow repolarization over several seconds. Potassium-induced depolarizations were conducted along arterioles, and the values of the electrical length constant for conducted depolarization determined by optical and microelectrode methods were in agreement. We conclude that ratio analysis of di-8-ANEPPS fluorescence emission can be used to accurately record membrane potential changes on the time scale of seconds during vasomotor activity from arterioles.

Congenital diaphragmatic hernia: experience in a single institution from 1978 through 1994.

BACKGROUND: Congenital diaphragmatic hernia continues to be a difficult management problem. Essentially all information on the condition has been compiled in a retrospective manner due to the individualized care that each infant must undergo. We contribute a review of our patients to add to the current fund of knowledge and to assess our experience before and since the introduction of extracorporeal membrane oxygenation in our institution. METHODS: This is a review of records of infants with congenital diaphragmatic hernia treated from 1978 through 1994. Repair has generally been accomplished early with only one repair being accomplished with an infant placed on extracorporeal membrane oxygenation preoperatively. RESULTS: Overall survival was 63%. Survival was 42% before extracorporeal membrane oxygenation becoming available in our region in 1986, and 75% afterward. Since 1986, 16 of 33 (48%) infants have required extracorporeal membrane oxygenation and 73% have survived. CONCLUSIONS: Overall survival in our series is comparable with that of other reported series. There appears to be an improvement in survival since the introduction of extracorporeal membrane oxygenation. Our present practice of early repair, and postrepair extracorporeal membrane oxygenation if needed, results in a survival rate comparable with that of currently available series reports regardless of the method of treatment reported.

Anesthetic techniques for pediatric thoracoscopy.

BACKGROUND: Since 1981, we have performed 68 thoracoscopic procedures in 62 patients aged 7 months to 21 years. METHODS: We reviewed the anesthetic and ventilation strategy used for each procedure to determine which anesthetic strategies are safe and effective for particular children and conditions. RESULTS: Regional anesthesia with sedation was used for six procedures in 5 patients with a mean age of 16 years (range, 9 to 21 years). One patient required conversion to general anesthesia. General anesthesia with one-lung ventilation was attempted for 18 procedures in 17 patients with a mean age of 12 years (range, 7 months to 18 years). Two patients required conversion to two-lung anesthesia secondary to pulmonary intolerance. One of these patients and 2 others required thoracotomy. General anesthesia with two-lung ventilation was used for 44 procedures in 41 patients with a mean age of 9 years (range, 1 to 17 years). There were no anesthesia-related difficulties. CONCLUSIONS: Regional anesthesia should be limited to the older, more cooperative patient. General anesthesia with one-lung ventilation is useful in adolescents, as they tolerate collapse of one lung well, and it is particularly desirable for procedures requiring exposure of the mediastinum and for talc pleurodesis. General anesthesia with two-lung ventilation can be used in any age group but is generally necessary for infants and small children, as they often will not tolerate the collapse of one lung, and in the larger child or adolescent with severe pulmonary compromise.

Management of transected pancreas in children.

The pancreas is the fourth most commonly injured intra-abdominal organ in children who sustain blunt abdominal trauma. Appropriate management of the injured pancreas has been controversial. With the advent of the computerized tomography scan, paediatric surgeons have tended to manage pancreatic injuries non-operatively. However, if pseudocysts develop, non-operative management may necessarily entail a long hospital course involving total parenteral nutrition, drainage procedures and attendant morbidity. The critical element in planning therapy is to determine the status of the pancreatic duct. We have recently encountered five children who suffered blunt pancreatic injury where the main pancreatic duct was determined to have been transected. These children underwent spleen preserving distal pancreatectomy with resultant shorter hospital stays and minimal long-term morbidity. We suggest that in children with pancreatic injury where the main pancreatic duct has been transected early operative management rather than non-operative therapy is the procedure of choice. Endoscopic retrograde cholangiopancreatography should be used to determine the status of the pancreatic duct. This modality can be both diagnostic and therapeutic in appropriate circumstances.

Colorectal carcinoma in patients 30 years of age and younger.

Thirty-seven cases of colorectal cancer in patients aged 30 years or younger have been treated at the University of Virginia Health Sciences Center from 1957 through 1992. The present series, comprising patients treated from 1978 through 1992, updates a series presented from our institution comprising patients treated from 1957 through 1977. For the 36-year series, 24 patients (65%) were female, and 13 (35%) were male. Sixteen patients (43%) were black, and 21 patients (57%) were white. Sites of tumor and their frequency were rectosigmoid, 14 (38%), left colon, five (14%), splenic flexure, two (5%), transverse colon, three (9%), hepatic flexure, two (5%), right colon, two (5%), and cecum, six (16%). Twenty-two patients (59%) presented with abdominal pain, whereas 15 (41%) presented with hematochezia or hemoccult positive stools. The average time of onset of symptoms to diagnosis was 2.3 months. Thirty-four of 37 patients (92%) presented with advanced stage disease. Only four patients had precancerous conditions: one each with Gardner's Syndrome, Turcot's Syndrome, ulcerative colitis, and villous adenoma. Twenty-five patients (68%) underwent surgery for cure, and ten (27%) received palliative procedures. Nothing could be done for two patients (5%). Twenty-one patients (57%) had mucinous histology, 13 (35%) had typical adenocarcinoma, one (3%) had small cell carcinoma, and histology was unavailable in two (6%). Nodes were negative in only 10 (27%) patients, of which only three had mucinous histology. There have been five 5-year survivors and three patients alive and disease free at last follow up, ranging from 30 months to 48 months.(ABSTRACT TRUNCATED AT 250 WORDS)

Use of video-assisted thoracic surgery in the treatment of chylothorax.

Chylothorax, a potentially lethal disorder that may cause profound respiratory, nutritional, and immunologic complications, has become increasingly common in recent years. Medical therapy has been found to have a significant failure rate. Therefore, surgical treatment of complicated chylothorax has become a mainstay of care. Between 1987 and 1993, ten patients at the University of Virginia Hospital were treated with video-assisted thoracic surgery for complicated chylothorax. Twelve thoracoscopic procedures were performed. Patients ranged in age from 7 months to 82 years. Causes included iatrogenic (2), congenital (2), caval thrombosis (2), amyloid (2), blunt trauma (1), and metastatic carcinoid tumor (1). In 10 cases, video-assisted thoracic surgery was employed as the principal mode of therapy: 8 using talc pleurodesis alone, 1 using talc pleurodesis and clipping of the thoracic duct with application of fibrin glue, and 1 requiring clipping of a pleural defect with application of fibrin glue. In 2 cases, a video-assisted thoracic operation was used in conjunction with pleuroperitoneal shunting: a previously placed pleuroperitoneal shunt that was malfunctioning was repositioned thoracoscopically after a pleural adhesiolysis, and a pleural adhesiolysis was performed thoracoscopically before placement of a pleuroperitoneal shunt. In all cases the effusion resolved after the video-assisted thoracic operation without further intervention. Video-assisted thoracic surgery offers an effective means of treating chylothorax, regardless of cause, allowing the advantage of access to thoracic structures without the morbidity of more extensive procedures.

The effects of talc pleurodesis on growing swine.

Talc pleurodesis is an effective means of preventing recurrent pneumothorax. We have successfully applied talc pleurodesis with thoracoscopy in children with cystic fibrosis presenting with pneumothorax. However, little is known about the effects of talc pleurodesis on lung compliance in growing children. Therefore, six young pigs (10 weeks old, weighing 15 +/- 1 kg) were prepared for study. In each pig, one hemithorax underwent thoracoscopy and talc pleurodesis (TALC). The other hemithorax underwent either thoracoscopy alone or no procedure (CONTROL). Dynamic and static respiratory mechanics were studied 5 and 10 weeks later. Air flow and airway pressure were measured to calculate dynamic transpulmonary and transrespiratory compliance, and static transpulmonary compliance. At 5 weeks, dynamic transpulmonary and transrespiratory compliance were less in the TALC lungs when compared with CONTROL lungs. At 10 weeks, the differences in dynamic transpulmonary and transrespiratory compliance between the TALC and CONTROL lungs had resolved. Static compliance was lower in the TALC lungs than in the CONTROL lungs at both 5 and 10 weeks, but this was significant only at 10 weeks. There was an improvement in static compliance in the TALC lungs between 5 and 10 weeks, but this only approached significance. At autopsy, there were marked adhesions and pleural thickening in the talc lungs. Histological examination demonstrated no differences in lung parenchyma between the TALC lungs and the CONTROL lungs. Talc pleurodesis causes a temporary impairment in dynamic transpulmonary and transrespiratory compliance that resolves with time and growth. Static compliance is more persistently compromised, but a trend toward improvement with time and growth exists.(ABSTRACT TRUNCATED AT 250 WORDS)

Decreased vascular compliance after reimplantation of the left lower lobe in young pigs.

The effects of chronic denervation on pulmonary vasculature are not well understood. Three groups of young pigs were prepared: (1) those receiving sham thoracotomy, (2) those having left upper lobectomy alone (innervated left lower lobe), and (3) those receiving left pneumonectomy followed by reimplantation of the left lower lobe (denervated left lower lobe). At 10 weeks after operation, animals were anesthetized and instrumented for study. No changes in baseline pulmonary artery pressure, pulmonary capillary wedge pressure, cardiac output, or pulmonary vascular resistance were observed. With diversion of the entire cardiac output to the left lung or lobe, however, the group with reimplanted lobes had a significantly higher pulmonary artery pressure and pulmonary vascular resistance than the other groups. This may result from chronic denervation of the pulmonary vasculature and receptor upregulation.

Laparoscopically applied fibrin glue in experimental liver trauma.

We have investigated the feasibility of applying fibrin glue to liver injuries using laparoscopic guidance and have examined the gross and microscopic changes that occurred in hepatic lacerations treated with fibrin glue. These studies indicate that fibrin glue may be effectively applied to liver injuries using laparoscopic control, hepatic bleeding may be rapidly controlled when fibrin glue is applied into the base of the wound, there is no gross or microscopic evidence of hepatic toxicity related to the use of fibrin glue, and healing of liver lacerations treated by fibrin glue occurs by ingrowth of granulation tissue coupled with fibrinolysis of the fibrin glue.