Fibrin glue reduces the severity of intra-abdominal adhesions in a rat model

BACKGROUND: The purpose of this study was to determine whether fibrin glue inhibits intra-abdominal adhesions. METHODS: Twenty rats underwent midline laparotomy. To maximize adhesions, bilateral peritoneal muscular defects were created and covered with polypropylene mesh sewn with a braided suture. The bowel was abraded with dry gauze. Rats were randomized to either fibrin glue (FG) sprayed over the mesh or to control (no further treatment) groups. At 1 week, the adhesion density (graded 0 to 3), the percentage of the patch covered by adhesion (0% to 100%), and adhesion type were recorded. RESULTS: The mean adhesion density was 1.45+/-0.33 for FG versus 2.8+/-0.11 for controls (P = 0.001). The mean percentage of adhesions was 36+/-9.9 for the FG group and 94+/-3.7 for controls (P = 0.0002). Bowel or solid organs were adherent to the patch in 6 of 20 (30%) in the FG group versus 12 of 20 (70%) in controls (P = 0.057). CONCLUSIONS: Topical fibrin glue reduces the density and severity of intra-abdominal adhesions in a rat model.     

Inhibition of intra-abdominal adhesions: a comparison of hemaseel APR and cryoprecipitate fibrin glue.

Our previous studies demonstrated fibrin glue (FG) prepared from cryoprecipitate (cryo) inhibits intra-abdominal adhesions in rats. A new FG, Hemaseel APR, is Food and Drug Administration (FDA) approved for hemostasis during cardiac surgery and splenic trauma. This study was undertaken to determine if Hemaseel FG prevents intra-abdominal adhesions, and to compare it to cryo FG. Forty-five rats underwent laparotomy. Bilateral peritoneal-muscular defects were created. Polypropylene mesh was sewn into each defect with a running silk suture. The bowel was abraded with gauze. The rats were then randomized to mesh covered with Hemaseel FG, cryo FG, or control. On postoperative day 7, the severity of adhesions were graded by percentage of mesh covered by adhesion (0-100%) and degree of adhesion (0-3). The mean percentage of mesh covered by adhesion was 9% for Hemaseel FG, 43% for cryo FG (p = .005), and 65% for the controls (p < .0001). The mean density adhesion score was 0.5 for Hemaseel FG, 1.2 for cryo FG (p = .04), and 2.1 for the controls (p < .0001). In the Hemaseel FG group, 77% of patches had no adhesions, compared with 37% in the cryo FG group (p = .004) and 13% in the controls (p < .0001). Thus, Hemaseel FG significantly decreases intra-abdominal adhesions, and is more effective than cryo FG.     

Inhibition of Intra-Abdominal Adhesions: A Comparison of Hemaseel APR and Cryoprecipitate Fibrin Glue

Our previous studies demonstrated fibrin glue (FG) prepared from cryoprecipitate (cryo) inhibits intra-abdominal adhesions in rats. A new FG, Hemaseel APR, is Food and Drug Administration (FDA) approved for hemostasis during cardiac surgery and splenic trauma. This study was undertaken to determine if Hemaseel FG prevents intra-abdominal adhesions, and to compare it to cryo FG. Forty-five rats underwent laparotomy. Bilateral peritoneal-muscular defects were created. Polypropylene mesh was sewn into each defect with a running silk suture. The bowel was abraded with gauze. The rats were then randomized to mesh covered with Hemaseel FG, cryo FG, or control. On postoperative day 7, the severity of adhesions were graded by percentage of mesh covered by adhesion (0-100%) and degree of adhesion (0-3). The mean percentage of mesh covered by adhesion was 9% for Hemaseel FG, 43% for cryo FG (p = .005), and 65% for the controls (p &lt; .0001). The mean density adhesion score was 0.5 for Hemaseel FG, 1.2 for cryo FG (p = .04), and 2.1 for the controls (p &lt; .0001). In the Hemaseel FG group, 77% of patches had no adhesions, compared with 37% in the cryo FG group (p = .004) and 13% in the controls (p &lt; .0001). Thus, Hemaseel FG significantly decreases intra-abdominal adhesions, and is more effective than cryo FG.     

Fibrin gel limits intra-abdominal adhesion formation.

Autologous fibrin gel (FG) has recently been reported efficacious in hepatic injury; the effects of fibrin compounds on intra-abdominal adhesion formation is controversial. This study evaluated intra-abdominal adhesion formation in a rabbit devascularization model. Seventeen New Zealand rabbits were anesthetized and laparotomy was done. The uterine horns were abraded to punctate bleeding followed by bilateral uterine devascularization. Treatment consisted of 10 cc saline control (c) or FG applied to the uterine horns. Peritoneal lavage was done at 15 minutes for red blood cell (RBC) analysis. Autopsy was performed at 1 week. Adhesions were graded from grade 0 (no adhesions) to grade III (dense adhesions). Adhesion grading revealed no difference in average adhesion grade between FG and C with small bowel (1.0 +/- 1.3 vs 0.5 +/- 1.0); bladder (2.1 +/- 1.1 vs 2.4 +/- 1.2); or uterus (1.2 +/- vs 2.0 +/- 1.2). Adhesion grade was significantly less in FG compared to C for the colon and the abdominal incision (0.4 +/- 0.5 vs 1.7 +/- 1.1 and 1.2 +/- 1.1 vs 3.0 +/- 1.2; P less than 0.05 by t-test). There were no differences in lavage RBC count between FG and C (13.1 x 106 +/- 4.1 x 10(6) vs 8.7 x 106 +/- 3.2 x 10(6)). Fibrin gel significantly decreased incisional and colonic adhesions and reduced other abdominal adhesion formation by a nonhemostatic dependent mechanism.     

Influence of the platelet-activating factor receptor antagonist BB-882 on intra-abdominal adhesion formation in rats

Postoperative intra-abdominal adhesion formation is a major clinical problem. We aimed to examine the preventive effect of treatment with the platelet-activating factor (PAF) antagonist (lexipafant, BB-882) on experimentally induced intra-abdominal adhesion formation in rats. Twenty male Sprague-Dawley rats weighing 250 and 290 g were studied. Generation of adhesions in rats by brushing a 1-cm(2) area of the cecum and the peritoneum on the right side of the abdominal wall was followed by intra-abdominal administration of saline and 5 mg/kg in a volume of 0.2 ml PAF receptor antagonist BB-882. After 45 days, formation of adhesions was graded and histological evaluation was processed. The severity of adhesions was significantly less in the BB-882 group than in the control group (p < 0.001, p < 0.05). The average adhesion scores in the control and BB-882 groups were 3.2 +/- 0.6 and 0.6 +/- 0.6, respectively, and the difference between both groups was found to be significant (p < 0.0001). The number of polymorphonuclear leukocytes and fibrotic areas was significantly decreased in the BB-882 group when compared to the control group (p < 0.001, p < 0.002). In conclusion, this study confirms the efficacy of BB-882 in the prevention of postoperative intra-abdominal adhesions in a rat model.     

A clinical comparison of Dacron patch closure of small-caliber carotids compared with primary closure of large-caliber carotids after endarterectomy

The objective was to study results of carotid endarterectomies performed between 1975 and 1991, comparing primary closure to Dacron patch closure. This was a retrospective study. Data from patient follow-up by physical examination, chart review, and Duplex study were used. Scan data were obtained in 92 of the primary cases, at a mean of 5 years postoperatively, and in 63 of the patch cases, at a mean of 4.1 years postoperatively. During this period, 269 endarterectomies were closed primarily and 101 were closed with a knitted Dacron patch. Twenty patients in the primary group and nine patients with patch closure were lost to follow-up, which extended for up to 12.5 years, with a mean of 4.7 +/- 3.6 years. No acute closures, infections or aneurysms developed in either group. Perioperative stroke incidence was 4.1 per cent for primary closure and 3.0 per cent for the patch group (P > 0.05). Late stenosis occurred in 17.3 per cent of the primary group and 11.1 per cent of the patch closure group (P > 0.05). Five-year survival was 76.2 per cent in the primary group, compared with 79.2 per cent for patch closure. Late stroke incidence was 2.8 per cent in the primary group and 3.3 per cent in the patch closure group. Results of smaller (< or = 3.5 mm) carotid arteries closed with knitted Dacron patches are equivalent to those of larger carotid arteries closed primarily.     

Outcome of patients with rectal cancer treated by stapled anterior resection

The mortality, morbidity and long-term survival in stapled anterior resection for rectal carcinoma has been analysed in 74 patients. Twelve patients were Dukes' A, 26 B, 29 C, and 7 'D' (submitted to hepatic resection). Operative mortality rate was 3 per cent. Three patients (4 per cent) had clinical anastomotic leakage. Two patients (3 per cent) developed anastomotic stenosis. Local recurrence was present in three patients (4 per cent). The mean (+/- s.e.m.) overall survival rate at 5 years was 67 +/- 6 per cent. There was no significant difference in survival between Dukes' B and C (70 +/- 10 per cent versus 59 +/- 10 per cent, P = 0.209). Patients with absent local spread had a significantly better 5-year survival rate than those with positive local lymph nodes (80 +/- 7 per cent versus 54 +/- 9 per cent, P less than 0.01). The present results confirm the satisfactory use of the EEA stapler device for colorectal anastomoses in rectal cancer and in patients with resectable liver metastasis.     

Renal toxicity of interleukin-2 administration in patients with metastatic renal cell cancer: effect of pre-therapy nephrectomy

Systemic administration of interleukin-2 and lymphokine-activated killer cells is a new approach to the immunotherapy of advanced cancer. Metastatic renal cell cancer is one of the histological types of tumors particularly susceptible to this treatment approach although renal toxicity often is a dose-limiting side effect. We compared the renal functional changes observed during interleukin-2 therapy in 52 consecutive patients with advanced renal cancer to that of 83 consecutive patients with metastatic nonrenal cancer. Of the 52 patients with renal cancer 41 had recently undergone nephrectomy. The over-all peak serum creatinine values and the percentage increase of serum creatinine over baseline for all patients studied were significantly higher in cycle 2 of interleukin-2 therapy than in cycle 1: 3.8 +/- 0.2 versus 2.6 +/- 0.1 mg. per dl. and 241.7 +/- 16.5 versus 140.3 +/- 11.0 per cent, respectively. In patients with pre-therapy serum creatinine values of 0.4 to 0.9 mg. per dl. there were no significant differences in the mean peak serum creatinine nor in the percentage increase over baseline between renal and nonrenal cancer patients during cycle 1. In cycle 2 of therapy these values were higher in the renal cancer group (3.6 +/- 0.8 versus 2.4 +/- 0.2 mg. per dl. and 310.4 +/- 103.5 versus 214 +/- 30.4 per cent, respectively) but they did not reach statistical significance (P2 = 0.08 and 0.25, respectively). Renal and nonrenal cancer patients with pre-therapy serum creatinine levels of 1.0 to 1.4 mg. per dl. achieved similar high values in cycle 2 of interleukin-2 therapy (3.9 +/- 0.3 versus 3.9 +/- 0.4 mg. per dl. and 222.7 +/- 23.2 versus 248.7 +/- 33.5 per cent, respectively), although the initial increase (cycle 1) was higher in the renal cancer patients (3.3 +/- 0.3 versus 2.4 +/- 0.2 mg. per dl. and 172.3 +/- 25.9 versus 116.1 +/- 18.0 per cent, respectively). Baseline serum creatinine greater than or equal to 1.5 mg. per dl. was associated with an over-all higher peak serum creatinine and higher percentage increase of serum creatinine over baseline than that below 1.5 mg. per dl. baseline: 4.4 mg.per dl. and 171.1 +/- 36.3 per cent in cycle 1 and 6.5 +/- 0.7 mg. per dl. and 296.1 +/- 44.0 per cent in cycle 2, respectively (p less than 0.01). There was no association between peak serum creatinine and interval from nephrectomy to interleukin-2 therapy.(ABSTRACT TRUNCATED AT 400 WORDS)     

Halothane depresses baroreflex control of heart rate in man.

Baroreflex control of heart rate was determined during three awake control situations and during two depths of halothane anesthesia in man. Baroreflex function was quantiated by calculating the pressor test slope from the R-R interval change on the ECG produced by a pharmacologically induced pressor response. During the three awake control situations the subjects breathed room air or 100 per cent O2 spontaneously or 100 per cent O2 with ventilation controlled. Mean (+/- SD) slopes obtained were 15.1 +/- 4.5, 15.6 +/- 6.8 and 18.4 +/- 9.9, respectively. No significant difference in baroreflex function slope was observed. During light halothane anesthesia (0.7 per cent endtidal) baroreflex function was significantly depressed (mean slope = 2.5 +/- 1.5), and it was abolished at 1.1 per cent end-tidal halothane (mean slope = 0.03 +/- 0.04). It is concluded that halothane anesthesia produces depression of baroreflex control of heart rate in man.     

Pericardium as a thoracic aortic patch: glutaraldehyde-fixed and fresh autologous pericardium

The repair of complex coarctation of the aorta often requires an aortic patch. Prosthetic patches lack growth potential and are associated with an increased incidence of aneurysm formation opposite the patch. We compared buffered glutaraldehyde-fixed patches, used in six animals (group 1), and untreated autologous pericardial aortic patches, used in five animals (group 2). Weanling pigs underwent pericardial patch replacement of a 1 X 2-cm diamond-shaped segment of the lateral wall of the descending thoracic aorta at the level of the aortic isthmus. Six months following patch aortoplasty, the animals were killed and the in situ patch dimensions were measured and compared to the measurements obtained at implantation. The increases in length, recorded as mean percentage change +/- SEM, were 34.7 +/- 3.7% for group 1 and 102.8 +/- 20.3% for group 2 animals; the increases in width were 91.4 +/- 31.7% for group 1 and 192.4 +/- 31.4% for group 2. The percentage changes for both length and width were significantly different between groups (P less than 0.05). Pull strength testing of standard-size patch samples demonstrated no significant difference in tensile breaking load between groups: group 1 = 959 +/- 277 g, group 2 = 795 +/- 86 g. Thoracic aortography revealed no evidence of stenosis or aneurysmal dilation in either group. Autologous pericardium is resilient, strong, and readily available and has expansile potential that makes it an ideal aortic patch material. We conclude that glutaraldehyde fixation does not provide additional strength and limits graft expansile potential when compared to untreated pericardium.     

Ten-year follow up after laparoscopic Nissen fundoplication for gastroesophageal reflux disease

Laparoscopic Nissen fundoplication was first undertaken in the early 1990s. Appreciable numbers of patients with 10-year follow up are only now available. This study assesses long-term outcome and durability of outcome after laparoscopic Nissen fundoplication for treatment of gastro-esophageal reflux disease. Since 1991, 829 patients have undergone laparoscopic fundoplications and are prospectively followed. Two hundred thirty-nine patients, 44 per cent male, with a median age of 53 years (+/- 15 standard deviation) underwent laparoscopic Nissen fundoplications at least 10 years ago; 28 (12%) patients were "redo" fundoplications. Before and after fundoplication, among many symptoms, patients scored the frequency and severity of dysphagia, chest pain, vomiting, regurgitation, choking, and heartburn using a Likert scale (0 = never/not bothersome to 10 = always/very bothersome). Symptom scores before versus after fundoplication were compared using a Wilcoxon matched-pairs test. Data are reported as median, mean +/- standard deviation, when appropriate. After fundoplication, length of stay was 2 days, 3 days +/- 4.8. Intra-operative inadvertent events were uncommon and without sequela: 1 esophagotomy, 1 gastrotomy, 3 cardiac dysrhythmias, and 3 CO2 pneumothoraces. Complications after fundoplication included: 1 postpneumonic empyema, 3 urinary retentions, 2 superficial wound infections, 1 urinary tract infection, 1 ileus, and 1 intraabdominal abscess. There were two perioperative deaths; 88 per cent of the patients are still alive. After laparoscopic Nissen fundoplication, frequency and severity scores dramatically improved for all symptoms queried (P < 0.001), especially for heartburn frequency (8, 8 +/- 3.2 versus 2, 3 +/- 2.8, P < 0.001) and severity (10, 8 +/- 2.9 versus 1, 2 +/- 2.5, P < 0.001). Eighty per cent of patients rate their symptoms as almost completely resolved or greatly improved, and 85 per cent note they would again have the laparoscopic fundoplication as a result of analysis of our initial experience, thereby promoting superior outcomes in the future. Nonetheless, follow up at 10 years and beyond of our initial experience documents that laparoscopic fundoplication durably provides high patient satisfaction resulting from long-term amelioration of the frequency and severity of symptoms of gastroesophageal reflux disease. These results promote further application of laparoscopic Nissen fundoplication.     

Repeat sternotomy after reconstruction of the pericardial sac with glutaraldehyde-preserved equine pericardium

The risk of repeat sternotomy is higher than that of the initial sternotomy, especially if the pericardial sac was left open at the first intervention. In 200 consecutive patients with a pericardial defect after open heart operations, the pericardium was closed with a glutaraldehyde-preserved equine pericardial patch. Precardiac adhesions at reoperation were assessed in four groups of patients on a scale of 6, ranging from 0 (no adhesions) to 5 (calcified or ossified adhesions). Group I comprised 13 patients in whom the pericardium was left open at the first operation and an equine pericardial patch was implanted at reoperation. Group Ia included the first five Group I patients who underwent reoperation less than 1 year (early reoperation) after the initial procedure. Group Ib included the other eight patients of Group I, who underwent reoperation more than 1 year (late reoperation) after the first procedure. Group II comprised nine patients who were reoperated on after reconstruction of the pericardial sac with a glutaraldehyde-preserved equine pericardial patch. After a mean follow-up of 20.2 months, the incidence of patch-related complications was 1%. Statistical analysis shows less severe adhesions on reoperation in Group II patients (pericardial defect patched) than in Group I patients (pericardial defect left open): mean grade of adhesions 1.6 +/- 0.9 (Group II) versus 3.2 +/- 0.6 (Group I), p less than 0.001. Precardial adhesions with the pericardium left open were similar in patients having early and late reoperations: mean grade of adhesions 3.0 +/- 0.7 (Group Ia) versus 3.4 +/- 0.5 (Group Ib), no significant difference. Therefore, the glutaraldehyde-preserved equine pericardial patch can be considered a suitable material for primary closure of the pericardial sac in patients with inadequate autologous pericardium.     

Prevention of intraperitoneal adhesions: a comparison of noxythiolin and a new povidone-iodine/PVP solution.

Peritoneal adhesions were induced in 250 female Wistar rats by the excision and closure of a right lower quadrant parietal peritoneal defect. After closure of the defect each rat was randomly allocated to one of five treatment groups: A, control with no instillate; B, control with Ringer solution; C, noxythiolin 0.5 per cent solution; D, noxythiolin 1 per cent solution; E povidone-iodine/PVP solution. Two millilitres of the appropriate solution were injected into the peritoneal cavity just before closure of a standard 4-cm midline incision. Assessment of adhesion formation was made at 1 week in ignorance of the treatment group. Noxythiolin 1 per cent was more effective than Ringer solution and noxythiolin 0.5 per cent in reducing the mean number of adhesions (P less than 0.05) but was inferior to povidone-iodine/PVP (P less than 0.05). Povidone-iodine/PVP solution significantly reduced the number of adhesions compared with the four other groups. In addition, it significantly reduced the mean length of attachment of each adhesion compared with the two control groups (P less than 0.001).     

Is Fournier's gangrene severity index useful for predicting outcome of Fournier's gangrene?

OBJECTIVES: Fournier's gangrene (FG) is a rare but life-threatening disease. Although antibiotics and aggressive debridement have been broadly accepted as the standard treatment, the mortality rate remains high. We conducted a retrospective study to analyze the outcome and identify the risk factors and prognostic indicators. METHODS: We retrospectively reviewed the medical records of 25 patients diagnosed with FG between July 1993 and August 2003. Data collected included age, predisposing factors, treatment modalities, length of hospital stay, surgical debridement times, and outcome. The FG severity index was used to predict outcome. Univariate analysis of the different prognostic factors was performed using t test and Fisher's exact probability test. RESULTS: All patients were male, 60% were diabetic, and the mean age was 55.8 years. The mean hospital stay was 20 days and the mortality rate was 32%. The mean age of 53.8+/-18.3 (SD) years in the survival group (n=17) was significantly lower than the 59.9+/-10.2 years (n=8) of the non-survival group (p<0.05). Non-survival group patients had lower serum hematocrit (mean 28.9, p=0.019) and albumin (mean 1.93, p=0.024) levels. In our series, the mean FG severity index for survivors was 4.41+/-2.45 (range 2-9) compared to 12.75+/-2.82 (range 9-18) for those who died (t test, p<0.0001). CONCLUSION: The survival rate of younger patients with FG was higher. We agree that a FG severity index cutoff value of 9 is an excellent predictor of outcome.     

Role of fibrinolysis in the formation of postoperative adhesions

It has been hypothesized that peritoneal hypofibrinolysis is of importance in the formation of postoperative adhesions, but results from experiments with fibrinolytic modulators are conflicting. We tested this hypothesis in a controlled prospective study in rabbits, comparing the effects of fibrinolytic inhibition (tranexamic acid) to fibrinolysis enhancement by local instillation of gel containing tissue-type plasminogen activator. Adhesion formation was measured after 1 week in a strictly standardized way and is presented as a percentage of an induced lesion that was covered by adhesions. Fibrinolytic inhibition significantly increased adhesion formation, both to the parietal peritoneum (34.2%+/- 3.2%) compared with untreated control (19.7%+/- 3.3%, p < 0.01) and to the bowel (76.3%+/- 5.8%) compared with untreated control (51.2%+/- 8.7%, p < 0.05). Control gel significantly increased adhesions to the parietal peritoneum (35.6%+/- 4.6%) versus untreated control (19.7%+/- 3.3%, p < 0.05), whereas gel containing tissue-type plasminogen activator significantly reduced the amount of adhesions to the parietal peritoneum (4.9%+/- 1.7%) compared with untreated control (19.7%+/- 3.3%, p < 0.01) and abolished adhesion formation to the injured bowel. The fibrinolytic system thus seems to be intimately involved in the early formation of intraabdominal adhesions.     

Histochemical properties of muscle allografts enhanced via cyclosporine

Until recently, the transplantation of skeletal muscle across a major histocompatibility barrier has proved difficult. However, with the advent of cyclosporine (CsA), it has become possible to achieve extended survival across such histocompatibility barriers. To date, very little is known about the histochemical, biochemical, immunological or contractile properties of long-term-surviving muscle allografts. Consequently, it was the focus of this study to histochemically examine muscle allografts prolonged with CsA and determine the cross-sectional area of fast glycolytic muscle fibers. Measurements of cross-sectional area were made because they are an important correlate to the amount of tension a muscle can generate. Animals were assigned randomly to one of three groups: control (normal) (n = 5), syngeneic (n = 4), and allogeneic (n = 4). Muscle allografts were performed by transplanting the gastrocnemius of an ACI rat (RT1a) hindlimb into the hindlimb of a Lewis rat (LEW;RT1(1]. The syngeneic model consisted of an ACI-to-ACI transplant. Animals in the allograft group were given CsA (8 mg/kg/day) until the time of sacrifice. At approximately 100 days following transplantation, both syngeneic and allogeneic muscles were removed from the recipient, and quickly frozen in isopentane cooled by liquid nitrogen. Muscle fibers were classified as slow-oxidative (SO), fast-oxidative-glycolytic (FOG), or fast-glycolytic (FG) based upon their staining for myofibrillar ATPase and NADH-dehydrogenase. From each muscle, the cross-sectional area of approximately 175 FG muscle fibers was determined. The fast-glycolytic muscle fibers of both the syngeneic and allogeneic grafts demonstrated a substantial decrease in cross-sectional area. The mean value (+/- SD) for the fibers of the allografted muscle was 1165 +/- 533 microns 2. The mean (+/- SD) fiber cross-sectional area for the fibers of the syngeneic muscle was 973 +/- 421 microns 2. These values contrast with a mean (+/- SD) value of 3552 +/- 601 microns 2 for fibers from age-matched control animals. The differences between the syngeneic and allogeneic muscles were not significant (P greater than 0.05). However, both exhibited significant (P less than 0.01) atrophy compared with the control muscle.     

Dose-response and plasma concentration-response relationships of pancuronium in man.

The dose-response and plasma concentration-response relationships for pancuronium in man were studied during its intravenous administration to eight patients at a rate of 1.62 microgram/kg/min. The (log) dose-response relationships resulted in a sigmoid curve that was linear in its central range. At 20, 50 and 80 per cent paralysis the cumulative dosages (mean +/- SEM) were 0.04 (+/- 0.01), 0.06 (+/- 0.01), and 0.08 (+/- 0.02) mg/kg, respectively. Administration of pancuronium, 56 microgram/kg, to another 12 patients at a more rapid rate resulted in a maximum intensity of blockade of more than 50 per cent. The (log) plasma concentration-response curve was not parallel to the dose-response curve, with mean (+/- SEM) concentrations at 20, 50 and 80 per cent paralysis of 0.21 (+/- 0.04), 0.25 (+/- 0.04), and 0.30 (+/- 0.04) microgram/ml, respectively during the onset of paralysis. Following cessation of the infusion, plasma concentrations of pancuronium were usually lower for the same intensity of paralysis. Using data for the entire response range during recovery from paralysis, the mean effective plasma concentration of pancuronium for a 50 per cent response was 0.20 microgram/ml. Recovery from blockade to 95 per cent paralysis (5 per cent of control twitch height) was associated with a plasma concentration of 0.25 microgram/ml, a value in agreement with plasma concentrations obtained following a single bolus administration of pancuronium, 6 mg, to 30 patients. For 27 patients the rate of decline of paralysis from 80 to 20 per cent showed a highly statistically significant relationship to the apparent rate of decline in the plasma concentrations of pancuronium.     

Laparoscopy or scanning in oesophageal and gastric carcinoma?

A prospective study was undertaken of the accuracy in diagnosing intra-abdominal metastatic disease of the liver by scintigraphy, ultrasound scanning and laparoscopy. The effect of laparoscopy on management was also studied. Fifty patients were studied: 23 oesophageal carcinoma, 14 gastric carcinoma and 13 with suspected intra-abdominal metastatic spread. Accuracy was determined by laparoscopic biopsy, laparotomy and autopsy. The accuracy was 72 per cent for scintigraphy, 75 per cent for ultrasound and 96 per cent for laparoscopy (with 10 per cent failed ultrasound due to intra-abdominal gas). There was no morbidity or mortality associated with laparoscopy, with one failure due to adhesions. Thirteen patients without hepatic metastases had nodal and/or peritoneal spread diagnosed only by laparoscopy. Laparotomy was avoided in 58 per cent, and 74 per cent died in the 18 month follow-up period. Laparoscopy can obviate the need for laparotomy in inoperable cases of oesophageal carcinoma and allow better planning for potentially curable surgery. In gastric carcinoma the value of laparoscopy is doubtful as a high percentage require at least palliative surgery.     

Recovery room oxygenation: A comparison of nasal catheters and 40 per cent oxygen masks

One hundred and sixty-one ASA physical status I-III patients undergoing elective surgery were evaluated using nasal catheters versus 40 per cent O2 venturi masks. Twenty-one per cent of the patients arrived in the recovery room with hypoxia as measured with a pulse oximeter (SaO2 less than 90 per cent). Fifteen minutes later all patients who arrived hypoxic were well oxygenated on their chosen oxygen therapy. Only one patient that arrived normoxic became hypoxic using a nasal catheter 15 minutes later. There was no statistical difference between patients given 40 per cent O2 by mask versus patients given oxygen by nasal catheter. The mean SaO2 for the group given 40 per cent O2 at 15 minutes was 96.7 +/- 2.15 per cent versus 96.6 +/- 2.48 per cent for nasal catheters. Nasal catheters are as effective as 40 per cent O2 masks for treating hypoxia in the recovery room. Obesity and age were statistically significant risk factors in the patients that arrived hypoxic. Patients were 47.4 +/- 15.6 years in the hypoxic group versus 38.3 +/- 15.6 years in the non-hypoxic group (p less than 0.001). Patients having an endotracheal tube with intermittent positive pressure ventilation or having a premedication were more apt to be hypoxic on arrival. These last two factors were closely associated and may reflect bias. The patient's gender, history of smoking, presence of obstructive lung disease, not including asthma, location of incision, or type of anaesthetic were not statistically significant risk factors.     

Postoperative vomiting following strabismus surgery in paediatric outpatients: spontaneous versus controlled ventilation

The study was designed to compare the frequency and severity of postoperative vomiting in paediatric out-patients receiving controlled ventilation (IPPV) or breathing spontaneously (SV) during anaesthesia for strabismus repair. One hundred and twenty unpremedicated children (ages 2-12 years) were studied in a randomized fashion. After intravenous induction of anaesthesia and tracheal intubation, patients breathed halothane 1-1.5 per cent inspired and N2O 66 per cent in O2 spontaneously (n = 60), or received IPPV, halothane 0.5-1 per cent, N2O 66 per cent, and pancuronium 0.05 mg.kg-1, which was reversed with neostigmine and atropine (n = 60). The incidence of vomiting with SV was 50 per cent (95 per cent confidence limits: 34.5-65.5 per cent) compared with 40 per cent (24.5-55.5 per cent) with IPPV (p greater than 0.25). Patients in the SV group experiencing emesis had longer operations than those not vomiting (mean +/- SEM = 1.5 +/- 0.1 vs 1.2 +/- 0.1 hours, p less than 0.005). This was not the case with IPPV. There was no correlation between age, sex, duration of surgery, or number of extraocular muscles repaired, and frequency or severity of vomiting or time to discharge. No significant advantage was afforded by IPPV over SV in the present study.