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Biomedical subjects

M K Ferguson

Publications and source records attributed to M K Ferguson.

At least 109 records · Page 6Linked to original sources
PubMed1986

Physiologic evaluation of esophageal function in patients with achalasia and diffuse esophageal spasm.

To evaluate function of the normal and pathologic esophageal body under more physiologic conditions than those utilized for traditional laboratory testing, manometry was performed before and during eating using a catheter assembly containing three peripheral transducers. Studies were evaluated from seven normal volunteers, 18 typical achalasia patients (eight before and 10 after esophagomyotomy), and eight patients with diffuse esophageal spasm (DES) as characterized by frequent simultaneous and repetitive contractions. In the preprandial period, all had similar frequencies of esophageal contractions, although there was a wide range. During eating, the frequency of contractions increased in all groups; however, the contraction frequency in unoperated achalasia patients, 12.7 +/- 5.0 contractions/min, significantly exceeded the frequency in normal volunteers of 4.9 +/- 1.3 contractions/min, p less than 0.01. The frequency was lower in operated achalasia patients, 9.4 +/- 6.5 contractions/min, but still exceeded that of normal volunteers, p less than 0.01. Patients with DES also had more frequent contractions, 10.5 +/- 9.7 contractions/min, than did the normal volunteers, p less than 0.01. The mean pressure of esophageal contractions for both achalasia groups was similar and was significantly lower than for the normal volunteers. Pressure in the DES patients was intermediate. It is concluded that patients with achalasia have lower pressure but more frequent contractions than normal volunteers during eating, and this spasm-like activity may be a more important pathophysiologic factor in their dysphagia than previously recognized. Esophagomyotomy does decrease the frequency of these contractions. Frequency, but not pressure, of contractions differs from normal in patients with DES.

Eating↗
PubMed1986

Selection of operation for esophageal cancer based on staging.

The concept of en bloc removal of tissue surrounding the esophagus was applied to intrathoracic esophageal cancers, and the first 80 cases were operated on by this technique between 1969 and 1981. Analysis of prognostic factors showed that only penetration through the esophageal wall and lymph node spread influenced survival. Since 1981, a new staging system based on wall penetration (W) and lymph nodes (N), as well as systemic metastases (M), and similar to the modified Dukes' system for colon cancer has been used to select patients before and during surgery for en bloc resection if favorable pathology (W1, N0, or N1) could be anticipated. When curative resection was not attainable, based on preoperative and operative staging, a standard esophagectomy was considered for relief of symptoms when necessary. From July 1981 to June 1984, 68 esophageal cancers were referred to us, and 31 were resected by the en bloc method, 21 by standard esophagectomy, and 16 were not resected. The success of preoperative staging was confirmed, as only nine of the 31 en bloc cases demonstrated both W2 and N2 pathology. The proportion of W2N2 cases subjected to en bloc esophagectomy was less (p less than 0.01) than that in the preceding series. This selection of cases showed a favorable deviation in the survival curve following en bloc esophagectomy since 1981 compared to the earlier interval. Patients treated by en bloc esophagectomy had a significantly greater survival than they did following standard esophagectomy at all time intervals after 6 months. There was no difference in hospital mortality or complications between the two operations. Further evidence for the value of the new staging system was shown by the significant difference in survival curves between those with favorable versus unfavorable staging and treated by en bloc esophagectomy. Among all cases resected between 1981 and 1984, 18-month survival in W1 stage was 67% compared to 35% for W2 disease. Survival with N0 disease was 58% versus 43% for N1 stage and 21% for N2 stage. The favorable survival rates after en bloc resection in those with limited (less than W2N2) disease support the concept of selecting patients for curative surgery based on preoperative and operative staging. Preoperative radiation therapy caused a significant decline in patient survival at 6 and 12 months and has been abandoned.(ABSTRACT TRUNCATED AT 400 WORDS)

Adenocarcinoma↗
PubMed1986

The microvascular response of the neonatal mesentery to hypertonic feedings.

Using intravital microscopy we studied the responses of the jejunal and ileal mesenteric microcirculation to hypertonic meals in neonatal piglets. Test meals were infused through a cannulated segment of proximal jejunum. The intestinal segments were observed under conditions of controlled temperature and humidity, and the velocity of red blood cells through mesenteric arterioles was measured and blood flow calculated. Jejunal flow was not altered from baseline by saline or hypertonic mannitol infusion, while significant increases in flow were observed during hypertonic glucose infusion (3.8 X 10(-6) versus 10.7 X 10(-6) ml/s, p less than 0.01). Jejunal glucose infusion did not cause shunting from the ileal microcirculatory bed. We conclude that the infusion of hypertonic glucose causes an increase in jejunal blood flow, but does not result in a change in ileal flow. The increase in flow is a local phenomenon related to glucose absorption in neonatal piglets.

Animals↗
PubMed1986

Pericardioscopy as adjunct to pericardial window.

A technique for pericardioscopy at the time of subxiphoid pericardial window was evaluated in 17 patients undergoing surgery for clinically suspected malignant pericardial effusion. Best results were obtained using a rigid mediastinoscope for inspection of the posterior and lateral pericardial surfaces. No complications ensued, although many patients experienced cardiac arrythmias which always resolved with removal of the scope. Pericardioscopy revealed cancer transgressing the pericardium near the pulmonary veins in one patient, and this would have been missed without pericardioscopy. Pericardioscopy confirmed palpable metastatic deposits on the inferior pericardial surface in two other patients. In 14 patients, pericardioscopy did not reveal malignancy, although four of these patients had both positive fluid cytologic findings and malignant infiltration of the pericardial biopsy. In one patient a palpable but not visible nodule was proved to be an extrinsic hepatic metastasis. Pericardioscopy is a safe intervention chiefly applicable in patients with central tumors and pericardial effusion in whom subxiphoid pericardial window is not clearly diagnostic at the time of surgery.

Adult↗
PubMed1986

The role of adjuvant therapy after resection of T1 N1 M0 and T2 N1 M0 non-small cell lung cancer.

Thirty-four consecutive patients with non-small cell lung cancer plus N1 nodal metastases (eight with T1 N1 M0 and 26 with T2 N1 M0) were retrospectively reviewed. Nineteen had adenocarcinoma, 11 had squamous disease, and four had large cell carcinoma. Eleven patients had surgical resection alone (32.3%), with a median survival of 13 months. Seven patients (20.6%) had resection followed by radiation therapy, with a median survival of 19.2 months. Sixteen patients (47.1%) had resection followed by radiation therapy and chemotherapy, consisting of cyclophosphamide, doxorubicin, methotrexate, and procarbazine. Median survival for the latter group was 45.5 months, significantly greater than for those treated with resection alone (p less than 0.005). We did not observe any relationship between survival and age, cell type, number or location of diseased hilar nodes, distance of tumor from the resected bronchial margin, tumor size, the presence or absence of visceral pleural involvement, or the type of resection performed. Resection in combination with adjuvant radiation therapy and chemotherapy offers improved median survival over resection alone in patients with T1 N1 M0 and T2 N1 M0 non-small cell lung cancer.

Adenocarcinoma↗
PubMed1986

Modified stage I (T1N0M0, T2N0M0), nonsmall cell lung cancer: treatment results, recurrence patterns, and adjuvant immunotherapy.

We analyzed 96 patients who had surgery with T1N0M0 or T2N0M0 nonsmall cell lung cancer (NSCLC) to identify survival rates and recurrence patterns in well-staged patients and to evaluate adjuvant therapy. Preoperative staging included chest x-ray, gallium 67 scanning, and bronchoscopy in all patients. At thoracotomy, multiple mediastinal lymph node sites were routinely sampled. The results included an operative mortality rate of 5.2%, and the actuarial 5-year survival rate of all patients was 70.0%. Survival of T1N0 (n = 44) and T2N0 (n = 47) patients was 72.1% and 68.3%, respectively (p = NS). Survival was not affected by type of surgery, cell type, sex, age, or race. Late death was due to recurrence in 12 patients, a new airway malignancy in three, and a noncancer problem in six. Disease recurred in 15 patients: four (9.1%) T1N0 patients versus 11 (23.4%) T2N0 patients, p less than 0.05. Recurrence was local in four patients and distant in 11. Second lung cancers developed in six patients at a mean interval of 65.7 months after resection. A prospective, randomized trial of systemic immunotherapy with bacillus Calmette-Guerin (BCG) skin scarification was carried out in 29 patients. Survival in those patients receiving BCG was 85.9% compared with 63.9% for control subjects (p = 0.075) and 69.6% for patients not in the study (p = 0.077). The following conclusions can be made: Resection for well-staged, modified stage I NSCLC results in a 5-year survival rate of 70%. Nearly half the deaths are unrelated to recurrence of the original cancer. Recurrences are more frequent in T2N0 patients, but there is no survival difference compared with T1N0 patients. Systemic recurrences are more frequent than local recurrences, and there is an appreciable incidence of second lung cancers. Adjuvant chemotherapy or radiation therapy does not seem justified, but systemic immunotherapy holds sufficient promise to warrant further investigation.

Adult↗
PubMed1986

Effect of incomplete obstruction on feline esophageal function with a clinical correlation.

This study was performed because of the observation of unexplained esophageal dysfunction in patients with incomplete esophageal obstruction. A Gore-Tex band, measuring 110% of resting esophageal circumference, was placed about the esophagus at the gastroesophageal junction of 17 cats to produce incomplete obstruction by limiting the normal distention that occurs with swallowing. Esophageal manometry was performed before surgery and at 1 and 4 weeks after surgery. Lower esophageal high-pressure zone pressure was not influenced, but sphincter relaxation was impaired. Evaluation of esophageal body contractions showed that simultaneous contractions increased from 0% before surgery to 68% at 1 week and 85% at 4 weeks after surgery (p less than 0.001 versus preoperative for both comparisons). The incidence of repetitive contractions increased from 3.1% before surgery to 10.5% at 1 week and 10.9% at 4 weeks after surgery (p = NS). The average contraction pressure decreased from 22.5 mm Hg before surgery to 13.9 mm Hg at 4 weeks after surgery (p less than 0.05). Barium swallows showed esophageal dilatation, that was confirmed on gross examination. Histologic examination was remarkable only for retention esophagitis. Sham surgery in three cats with identical mobilization of the gastroesophageal junction did not affect motility. Motility returned to normal after the band was removed in three cats. Manometric evaluation of 15 patients with distal esophageal peptic strictures and 17 patients with excessively tight antireflux repairs showed a significantly increased (p less than 0.001) frequency of simultaneous contractions, 35% and 34%, compared with the 2.1% of 25 normal subjects. The following conclusions can be drawn: Partial obstruction alters feline esophageal body function and these achalasia-like changes are reversible on relief of the obstruction and similar motility aberrations occur in patients because of mechanical or functional distal obstruction; this suggests that dysmotility can synergistically contribute to dysphagia.

Animals↗
PubMed1986

Regional accuracy of computed tomography of the mediastinum in staging of lung cancer.

To determine the regional accuracy of computed tomography of the mediastinum in staging lung cancer, we compared the results of preoperative computed tomographic staging to pathologic findings in lymph nodes taken at mediastinoscopy and/or thoracotomy in 61 patients. Twenty-two patients had adenocarcinoma, 24 had squamous cell carcinoma, eight had large cell tumors, and seven had small cell cancer or mixed cellular types. Sixteen patients had Stage I, eight had Stage II, and 37 had Stage III disease. Thirteen patients had mediastinoscopy only, and the remaining 48 patients had thoracotomy. Computed tomographic staging of the mediastinum as a whole had an accuracy of 88% with a negative predictive index of 96.1%. In examining the differential regional accuracy within the mediastinum we found results in the aortopulmonary window to be inferior to those of other regions, with an accuracy of 80% and a negative predictive index of 83.3%. The reliability of computed tomographic scan staging varied relative to cell type. The accuracy rate in adenocarcinoma was 94.7% compared to 70.6% in squamous cell carcinoma. Computed tomography is accurate for staging the mediastinum in lung cancer, and this accuracy holds over the regions of the mediastinum except the aortopulmonary window. Computed tomography is more accurate for staging adenocarcinoma than squamous cell cancer.

Adenocarcinoma↗
PubMed1986

Reoperation for failed antireflux operations.

UNLABELLED: Experience with gastroesophageal reflux in patients without prior operations has yielded understanding of pathophysiology, surgical techniques, and results. Less is known about patients with failed antireflux operations. This report of 61 patients undergoing repeat antireflux procedures addresses this issues. Not included are patients with gastroesophageal reflux after ulcer operations or with inappropriate antireflux operations for motility disorders. Group A patients (n = 34) had only one previous operation, Group B (n = 19) had two, and Group C (n = 8) had three or more. Group C had significantly (p less than 0.05) more dysphagia and less heartburn than Group A. This observation correlated with findings from manometry, pH testing, and endoscopy, which showed progressively worse esophageal body function and a greater incidence of severe esophagitis and esophageal leak, but less gastroesophageal reflux, in Group C than B and in Group B compared to A. Operative mortality was 4.9%. Repeat antireflux operations in the 58 survivors were as follows: Group A included 25 standard antireflux procedures and seven bowel interpositions, and 75% were transthoracic. Group B included 16 antireflux procedures and one bowel interposition, and 82% were transthoracic. Group C included four antireflux procedures and three interpositions, and all were transthoracic. Clinical results were excellent or good in 85% in Group A, 66% in Group B, and only 42% in Group C (A versus C, p less than 0.05). Surgical complications increased from 27% in Group A to 75% in Group C (p less than 0.05). CONCLUSIONS: Patients with one prior operation and recurrent gastroesophageal reflux are similar to patients with no prior operations. Results of repeat antireflux operations deteriorate with increasing operations because of impaired esophageal function and progressive tissue destruction. Therefore, second reoperations must be definitive and resection and reconstruction with healthy tissue considered. A transthoracic approach is preferable for first reoperations and mandatory after multiple antireflux procedures.

Adolescent↗
PubMed1985

Malignant superior vena cava obstruction reconsidered: the role of diagnostic surgical intervention.

The cases of 42 patients with malignant superior vena cava (SVC) obstruction were reviewed to evaluate clinical dogmas of prohibitive risk for invasive diagnostic procedures and need for urgent radiotherapy. Thirty-nine had carcinoma (35, bronchogenic and 4, other), and 3 had lymphoma. Lung cancer histology was squamous cell in 11, adenomatous in 10, large cell in 7, and small cell in 7. The SVC obstruction was always symptomatic, usually causing facial or cervical swelling, but there was no instance of SVC obstruction causing life-threatening problems such as cerebral or laryngeal edema. Twenty-two patients underwent bronchoscopy (11 flexible and 11 rigid) prior to radiotherapy without respiratory complications, and diagnostic tissue was obtained in 8. Also prior to radiotherapy, 29 invasive diagnostic procedures were performed: thoracotomy (1), mediastinotomy or mediastinoscopy (11), supraclavicular or scalene node biopsy (15), and percutaneous lung needle biopsy (2). Neither excessive blood loss nor serious complications occurred, and diagnostic tissue was obtained in 22 patients who received individualized therapy. Eight patients had urgent radiotherapy, which delayed diagnosis and specific therapy for two weeks to 6 months. For the 33 patients who underwent radiotherapy after development of the SVC obstruction, the obstruction clinically resolved spontaneously within fourteen days, independently of whether radiotherapy was begun immediately or was delayed. Median survival was 5.0 months and was not influenced by the dose or timing (early or late) of radiotherapy. We reached the following conclusions. First, although a grim prognostic sign, SVC obstruction is rarely life-threatening and typically resolves spontaneously, probably by development of venous collaterals.(ABSTRACT TRUNCATED AT 250 WORDS)

Bronchoscopy↗
PubMed1985

Current concepts in the management of postoperative chylothorax.

Thirteen patients required pleural drainage for postoperative chylothorax with an average duration of leakage of 36.9 days. Total protein and albumin levels, body weight, and peripheral lymphocyte counts all decreased substantially during the period of chylous leakage. Only 3 chylothoraces resolved with tube drainage and dietary management alone. Six patients required eight operations for control of chylothorax, and 4 patients, all of whom had cancer, died with a persistent leak. chylothorax is a debilitating postoperative complication resulting in an impaired immune system and nutritional state. Because it is associated with a 50% mortality in patients with cancer, early reoperation should be considered. Patients with benign underlying disease can be managed conservatively for longer periods. Control of potential chylous leaks at the time of original operation is vital, especially in patients with malignancies who have a predisposition toward leakage from sites other than the main thoracic duct.

Adolescent↗
PubMed1985

Esophageal emptying and acid neutralization in patients with symptoms of esophageal reflux.

Clearance of refluxed acid from the distal esophagus is due to bolus emptying and salivary neutralization of acid. We compared results of 24-hour pH monitoring with acid clearance tests (ACT) and radioisotope swallows (RIS) in 26 symptomatic patients to determine which of the components of acid clearance is better correlated with gastroesophageal acid reflux (GER). Seven of eight patients with GER had delayed esophageal emptying on RIS. Abnormal salivary clearance of acid was present in nine of 18 patients without GER, accounting for a high false-positive rate of ACT. Delayed esophageal bolus emptying, not deficient acid neutralization by saliva, is the predominant component of abnormal acid clearance in patients with GER. RIS is superior to ACT as part of the evaluation of reflux symptoms, and may prove to be a valuable screening test for this condition.

Esophagogastric Junction↗
PubMed1985

Diagnosis and management of synchronous lung cancers.

The findings in 28 patients with synchronous lung cancers are reviewed. Mediastinoscopy and systemic staging were performed to exclude the possibilities that one pulmonary lesion was metastatic from the other or that both represented systemic metastases from another tumor. Nineteen patients underwent resection of both tumors. Median survival was 25 months for four patients with definite Stage I synchronous cancers (no nodal involvement; different cell types, bronchoscopically separate endobronchial lesions or arising from separate foci of carcinoma in situ) and was 27 months for seven patients with possible synchronous Stage I cancers (no nodal involvement; similar cell types; located in separate lobes). Median survival was 11 months for 16 patients having Stage II or III lung cancer accompanied by a second synchronous lung cancer. In the absence of hilar or mediastinal nodal involvement and systemic metastases, synchronous tumors should be considered separate primaries when located in different lobes, even if they have similar histologic features. Prognosis of synchronous cancers is related to the presence or absence of nodal metastases. Pneumonectomy is the operation of choice for synchronous unilateral tumors. With bilateral tumors, sequential resection starting with the most advanced lesion is appropriate. Preservation of lung tissue without compromising the cancer operation is critical.

Adenocarcinoma↗
PubMed1985

Management of unintentional extubation during left pneumonectomy.

Unintentional extubation can occur during pneumonectomy. Reintubation is sometimes difficult due to the position of the patient. Satisfactory ventilation can be achieved by means of an endotracheal tube inserted into the open bronchial stump, allowing elective reintubation to be performed transorally.

Humans↗
PubMed1984

Esophageal carcinoma with respiratory tract fistula.

An experience with 27 patients with malignant respiratory tract fistula (RTF) is presented. The RTF was related to carcinoma of the thoracic esophagus in all the patients, involved the trachea in 11, left main bronchus in 7, right main bronchus in 3, and was more distal in 6 patients. Metastases were detectable in only four patients (15%) at the time of RTF diagnosis. Bronchoscopy examination in 13 patients prior to RTF development showed tracheobronchial invasion or impingement in all. The RTF was present at initial presentation in 11 patients (Group I), and developed after/during radiation therapy (RT) in 16 patients (Group II). Median survival from tumor diagnosis was 17 weeks in Group I and 37 weeks in Group II, while survival from RTF diagnosis was 16 weeks in Group I and II weeks in Group II.

Adult↗
PubMed1982

The effects of thermal injury on rat skeletal muscle microcirculation.

An intravital microscopic study of rat skeletal muscle microvasculature was undertaken to assess changes in peripheral blood flow distant from thermal injury following burning. We found a significant increase in RBC velocity and quantitative flow in arterioles of animals with major thermal injury (28% TBSA full-thickness burn) compared to flow in animals with minor burns (18% TBSA) and control animals. There was no evidence for arteriolar diameter changes, erythrocyte sludging, or leukocyte-endothelial adherence. Major thermal injury is associated with an increase in skeletal muscle arteriolar blood flow distant from the site of injury.

Animals↗