PubMed Health⌕ Search

Biomedical subjects

R J Mullins

Publications and source records attributed to R J Mullins.

At least 91 records · Page 5Linked to original sources
PubMed1988

Evaluation of endoscopy training in a general surgery residency.

To evaluate the gastrointestinal endoscopy training program, a survey of the 33 former chief residents, who finished our program in 1981-1986, was conducted. All 33 graduates responded; 22 graduates are general surgeons, 11 completed or are completing training in a surgical specialty. Eighteen of the 22 general surgeons routinely perform endoscopy in their practice. Graduates in cities with a population greater than 250,000 are as likely to perform endoscopy as the surgeons who live in smaller communities. Ninety one per cent consider endoscopy training to have been an important part of their surgical training. Based on this assessment, endoscopy training is an important part of a general-surgery residency.

Colonoscopy↗
PubMed1987

Hypertonic saline resuscitates dogs in endotoxin shock.

In this experiment we determined if infusions of hypertonic saline (HS, 1080 Na meq/liter) could resuscitate dogs in endotoxin shock as effectively as Ringer's lactate (RL, 130 Na meq/liter). Anesthetized dogs received iv 0.5 mg/kg of Escherichia coli endotoxin, and mean arterial pressure (MAP, mm Hg) decreased from 148 +/- 5 to 58 +/- 14 within 30 min. To resuscitate the dogs 13 meq/kg of sodium was intravenously infused over 90 min as either a 10% body weight load of RL (n = 5) or a 1.2% body weight load of HS (n = 5). Both solutions produced an equivalent hemodynamic resuscitation 3 to 4 hr postinfusion with an increase in MAP (RL, 119 +/- 4; HS, 108 +/- 7), the restoration of cardiac outputs to baseline (RL, 2.0 +/- 0.2; HS, 1.9 +/- 0.3 liter/min), and similar renal inulin clearances (RL, 48 +/- 16; HS, 44 +/- 7 ml/min). The net fluid gain (resuscitation fluid volume infused minus urine output as percentage of body weight) was much greater in the RL group (7.2 +/- 1.0%) than in the HS group (0.48 +/- 0.2%). Plasma volume (PV, percentage of body weight) was measured with Evans blue dye in these splenectomized dogs. The increase in PV in the RL dogs (1.25 +/- 0.04%) was slightly greater than the increase in the HS group (0.94 +/- 0.13). Prenodal skin lymph was collected from both hindpaws, and the fractional increase in skin lymph flow after RL (4.5 +/- 2.9) was greater than the increase in the HS group (1.7 +/- 0.3).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1987

Screening before surgery for colon neoplasms with a flexible sigmoidoscope by surgical residents.

The value of flexible sigmoidoscopy to screen for colorectal neoplasms was determined in asymptomatic patients. One hundred sixty men (mean age 61 +/- 10), who denied a change in bowel habits or blood in their stools and who had guaiac-negative stools, had flexible sigmoidoscopic examinations performed by surgical residents with little previous endoscopy experience, while a staff surgeon continuously viewed the resident's progress through a teaching scope. Forty-nine benign neoplastic polyps were removed from 21% of the patients. The examination was well tolerated in 93% of these patients who received no medications. Resident endoscopists who had performed more than 15 examinations were more likely to reach 50 cm (79%) than those with less experience. The authors conclude that surgical residents are able to safely and effectively screen for colorectal neoplasms with a flexible sigmoidoscope when supervised.

Adult↗
PubMed1987

Albumin and IgG in skin and skeletal muscle after plasmapheresis with saline loading.

The acute effect of removing plasma equivalent to 1.7% body wt and replacing it with saline equivalent to 10% body wt on the extravascular distribution of water, albumin, and immunoglobulin G (IgG) in skin and skeletal muscle was studied in anesthetized rabbits. The plasma protein concentration decreased by 43%. Prenodal lymph was collected from hindpaw skin or skeletal muscle. The extracellular and plasma volumes in excised tissue samples were measured using 51Cr-labeled ethylenediaminetetraacetic acid and 125I-labeled albumin, respectively. The protein spaces were calculated from measurements of endogenous albumin and IgG concentrations using immunochemical techniques. Lymph flow from both tissues increased more than twice control, whereas the lymph total protein concentration decreased to less than one-half control. Three to six hours after the saline infusion, the skin interstitial volume was 30% greater than control, whereas the extravascular masses of albumin and IgG were 20% greater than control. For muscle, the interstitial volume was twice the control value, whereas the extravascular masses of albumin and IgG were not significantly altered. There was a large decrease in the lymph protein concentration after acute plasmapheresis. However, there was not an acute decrease in the extravascular albumin or IgG masses from skin or skeletal muscle. This may be due to the presence of the collagen matrix and edema fluid.

Animals↗
PubMed1987

Increased skin lymph protein clearance after a 6-h arterial bradykinin infusion.

When bradykinin (0.15-0.28 micrograms.kg-1.min-1) was infused into both femoral arteries of 11 anesthetized dogs, skin lymph flows increased by 25-371% within 2 h, and mean lymph protein concentrations increased by one-third. To determine whether, in addition to the initial increase in permeability, a 6.5- to 10-h bradykinin infusion caused a sustained effect, the bradykinin infusion into one hindpaw was stopped after 2 h (2HR), whereas the contralateral hindpaw was infused continuously (CONT). Two hours after the bradykinin infusion was stopped, Ringer lactate equal to 10% of the dog's body weight was given intravenously to further increase lymph flow. After Ringer lactate infusion, increase in lymph protein clearance from the CONT hindpaws was greater than that from the 2HR hindpaws (change in clearance from before Ringer lactate infusion to final: 2HR, 6.9 +/- 1.4 to 8.8 +/- 1.1; CONT, 23.4 +/- 2.5 to 40.2 +/- 4.8 microliters/min). In the final lymph samples of the CONT, but not 2HR, hindpaws, the lymph-to-plasma ratio for immunoglobulin G and immunoglobulin M divided by the albumin lymph-to-plasma ratio exceeded the value of these ratios in the base-line samples. An intravenous bolus of Evans blue dye was given less than 2 h before the end of the experiment. The concentrations of dye in the final lymph samples were greater in CONT hindpaws (12.6 +/- 3.7% plasma equivalents) than in the 2HR hindpaws (1.1 +/- 0.5%). A continuous 6.5- to 10-h intra-arterial bradykinin infusion produced a sustained increase of transvascular protein clearance in skin that is consistent with a sustained increase in microvascular membrane permeability.

Animals↗
PubMed1987

Skin microvascular permeability after resuscitation with Ringer's lactate solution from endotoxin shock.

Skin microvascular membrane permeability was assessed in anesthetized dogs after resuscitation from endotoxin shock. Infusion of Ringer's lactate solution, in a volume equal to 7 per cent of the body weight, reversed hypotension produced by an intravenous injection of Escherichia coli endotoxin (0.5 milligrams per kilogram). The shock group was compared with a group of dogs not given endotoxin and infused with a similar dose of Ringer's lactate solution and a with control group of dogs. Prenodal lymph was collected from both hindpaws and three to four hours before ending an increase of 20 to 28 millimeters of mercury in venous pressure of the hindpaw was produced in one limb by tightening a tourniquet. This maneuver produced an increase in lymph flow associated with an increase in lymph protein flux that was similar in all three groups. The wet to dry tissue weight ratio of skin samples did not increase in the endotoxin group. Skin microvascular membrane permeability did not increase. The safety factors that helped to prevent edema after infusion of Ringer's lactate solution included an increase in lymph flow and sieving by the intact microvascular membrane which diluted the interstitial protein concentration.

Animals↗
PubMed1986

Bradykinin causes a prolonged increase in skin microvascular permeability.

Bradykinin is an endogenous inflammatory mediator, and its mechanism of action is incompletely understood. It is controversial whether bradykinin causes a sustained increase in microvascular permeability, or has only a transient effect. In anesthetized dogs intraarterial infusion of bradykinin (0.14 to 0.54 micrograms/kg/min) produced an immediate increase in flow of protein-rich, hindpaw lymph. After 210 min of bradykinin infusion lymph flow was threefold greater than baseline, lymph protein concentration remained doubled, and in a dose-related fashion bradykinin produced a sustained increase in lymph protein flux. Lymph flow was then further increased with venous hypertension, and after 4 hr lymph protein flux remained greater from the bradykinin paws than from the control paws. This sustained increase in protein flux indicates that bradykinin produces an increase in permeability at the microvascular membrane by a mechanism that is different from how the initial increase in permeability was produced.

Animals↗
PubMed1985

Vagotomy plus Bilroth II gastrectomy for the prevention of recurrent alcohol-induced pancreatitis.

Three retrospective reviews documenting a lessened frequency of acute recurrent alcohol-induced pancreatitis following vagotomy, with or without gastrectomy or gastroenterostomy, prompted a prospective evaluation of truncal vagotomy with Bilroth II gastrectomy as a means of preventing such exacerbations. Randomization between operation and encouragement to abstain from alcohol in patients with a history of more than one, but less than ten, acute bouts of alcohol-induced pancreatitis was set by odd-even digits in the hospital number. Of 176 patients admitted with acute alcoholic pancreatitis during 23 months of study, 49 were excluded because of too few or too many prior attacks. Another 61 refused to enter the study. At least one (average 1.9) recurrence requiring hospitalization was noted in 49, or 80%, of these patients on follow-up for 2 to 26 months (average 14 months). Of the 66 who consented to participate, 33 were randomized not to undergo operation and had almost identical recurrence statistics (i.e., an average of 1.7 recurrences in 24, or 73%). By contrast, only two of 31, or six per cent, allocated to operation have experienced a recurrence (p less than 0.001). Two who had been randomized were excluded because of persisting active pancreatitis.

Acute Disease↗
PubMed1985

Thrombophlebitis following a bullet embolus to the popliteal vein.

A patient who had a bullet embolus to the right popliteal vein developed an extensive thrombophlebitis from the popliteal to the common iliac vein. We suggest that following extraction of a bullet that has embolized to a major extremity vein, it may be necessary to anticoagulate the patient.

Abdominal Injuries↗
PubMed1985

Effects of changing inspiratory to expiratory time ratio on carbon dioxide elimination during high-frequency jet ventilation.

Clinical observations indicate that gas exchange during high-frequency ventilation can be improved by decreasing the inspiratory to expiratory time ratio (I/E). Decreasing I/E at a fixed frequency may therefore allow a reduction of tidal volume (VT) without affecting gas exchange. This decreased VT may result in lower airway pressures, and thereby reduce the incidence of barotrauma. In order to quantify the effects of I/E on gas exchange, the relationship between carbon dioxide elimination and VT was studied in 6 mongrel dogs at I/E of 1/2, 1/1, and 2/1. Ventilation was provided by a jet-type high-frequency ventilator using a frequency of 5 Hz and VT of 17 to 100% of the anatomic dead space. Carbon dioxide elimination was found to vary inversely with (I/E)0.9, corroborating the clinical observations. These data add further evidence that I/E may be a useful parameter in optimizing high-frequency ventilation and provide a quantitative relationship that can be used to predict the effect that altering I/E will have on gas exchange.

Animals↗
PubMed1985

Hepatic trauma: evaluation of routine drainage.

Routine drainage of liver wounds created by trauma has recently been challenged, prompting a prospective, randomized trial of drainage via a Penrose dam versus no drain in patients having emergency laparotomy for abdominal trauma. We excluded cases in which definite bile leak was noted at operation. Of 167 patients studied, six had obligatory drainage because of obvious bile leak. Among the remaining 161 patients, there was no significant difference as to demographics, mode of injury, volume of blood lost or used for resuscitation, incidence and severity of shock, number and types of associated injuries, or magnitude of liver wound between the 78 allocated to drainage and the 83 left without a drain. Resultant mortality, duration of hospitalization, incidence of wound and/or intra-abdominal infection, and likelihood of subsequent bile fistula were not different. Such data support the routine use of a drain only if bile leakage from the liver wound is found at laparotomy. Without obvious bile leak, drainage of a specific liver injury does not appear to be necessary.

Adolescent↗
PubMed1984

Ceftriaxone versus combined gentamicin and clindamycin for polymicrobial surgical sepsis.

During a 7 month trial for therapy of polymicrobial surgical sepsis, intravenous antibiotic treatment was randomized between gentamicin (1 mg/kg every 8 hours) plus clindamycin (8 mg/kg every 6 hours), and the cephalosporin, ceftriaxone (1 g every 12 hours) in 197 patients, of whom 99 were being treated for peritonitis, 93 for soft tissue sepsis, and 5 for other forms of infection. No significant differences were noted in patient demographics, type of sepsis, associated disease states, surgical procedure, or causative aerobic or anaerobic pathogens. Results demonstrated approximately equivalent efficacy, although cure rates obtained with ceftriaxone in patients with soft tissue sepsis or intraabdominal abscess were superior to those achieved with combination gentamicin and clindamycin. There were no significant side effects with ceftriaxone therapy, such as the renal failure noted in six of the patients treated with gentamicin and clindamycin. We conclude that single agent treatment with ceftriaxone is preferable because of the greater safety and the longer dosing intervals.

Abdomen↗
PubMed1984

Mechanisms of impaired renal function with PEEP.

Deterioration in renal function associated with positive end-expiratory pressure (PEEP) has been attributed to renal hypoperfusion from the fall in cardiac output and mean arterial blood pressure. Using a canine in vivo model, renal function was measured during control, zero end-expiratory pressure (ZEEP), and PEEP (5, 10, and 15 cm H2O) ventilatory cycles, while renal blood flow was maintained constant with a pump. High PEEP (15 cm H2O) led to a rise in renal vein pressure (RVP) and a fall in mean arterial pressure (MAP). PEEP resulted in no change in glomerular filtration rate (GFR) or solute exertion; however, free-water clearance (FWC) became less negative in the 15-cm H2O PEEP group. Intrarenal autoregulation maintains GFR during ventilation with PEEP when renal blood flow is constant, supporting the view that altered filtration and solute excretion clinically is secondary to changes in aortic pressure and renal perfusion.

Animals↗
PubMed1984

Extraperitoneal versus transperitoneal drainage of the intra-abdominal abscess.

Controversy as to whether the intra-abdominal abscess should be drained extraperitoneally or through formal laparotomy still rages. Arguments for a transperitoneal approach include no need to identify specific locus preoperatively and uniform drainage of all abscesses, especially any otherwise unrecognized pus collection. Proponents for the extraperitoneal route stress failure to contaminate previously uninvolved peritoneal spaces and more reliable avoidance of injury to intestine, predisposing to subsequent intestinal fistula. To resolve this impasse, a prospective study of each method was based upon a schedule of previously randomized treatment options. After 32 months of study, 60 patients had been enrolled without obvious differences between treatment groups with respect to demographic features, preoperative definition and locus of infection, precipitating cause of sepsis, associated diseases, responsible bacteria and antibiotic therapy. With the transperitoneal approach, five patients had hollow viscus injury, while seven eventually had an intestinal fistula develop, causing major problems in four. Despite no obvious intestinal injury with the extraperitoneal route, two transient intestinal fistulas did occur. Seven patients drained transperitoneally had additional abscesses discovered, yet another operation was required to drain at least one complicating abscess in seven of this same group. With the extraperitoneal route, only two patients needed reoperation to drain another abscess. Although there were more deaths and complications in the group drained transperitoneally, morbidity (47 per cent) and mortality (7 per cent) were not significantly different statistically. Such data refute the professed superiority of a transperitoneal approach to intra-abdominal abscess drainage, both from need to reoperative for second abscess as well as incidence of latter intestinal fistula. Best results were noted with abscess identification through computerized tomography followed by extraperitoneal drainage.

Abdomen↗
PubMed1983

Management of the major coagulopathy with onset during laparotomy.

An experience with 31 patients who developed major bleeding diatheses during laparotomy was reviewed. Management of the initial 14 patients was by standard hematologic replacement, completion of all facets of operation, and then closure of the peritoneal cavity, usually with suction drainage; only one patient survived. The subsequent 17 patients had laparotomy terminated as rapidly as possible to avoid additional bleeding. Major vessel injuries were repaired; ends of resected bowel were ligated; and holes in other gastrointestinal segments and the bladder were closed by purse-string sutures. One patient had a ureter ligated. Laparotomy pads (4-17) were then packed within the abdomen to effect tamponade, and the abdomen was closed under tension without drains or stomata. Following correction of the coagulopathy, the abdomen was re-explored at 15 to 69 hours in the 12 survivors. Definitive surgery then was completed: bowel resection and reanastomosis; ureter reimplantation; drains for bile, pancreatic juice, and urine; and stomata for bowel or urine diversion or decompression. Eleven of 17 patients, deemed to have a lethal coagulopathy, survived. This technique of initial abortion of laparotomy, establishment of intra-abdominal pack tamponade, and then completion of the surgical procedure once coagulation has returned to an acceptable level has proven to be lifesaving in previously non-salvageable situations.

Adolescent↗
PubMed1983

Extravascular distribution of albumin and IgG during high-permeability edema in skin.

The effects of local intra-arterial infusions of bradykinin on the interstitial distribution of albumin and gamma-immunoglobulin G (IgG) was studied in hind paw skin of anesthetized rabbits. After 4 h of a continuous bradykinin infusion, lymph flow in a prenodal popliteal lymphatic was five times base line. The lymph-to-plasma concentration ratio for total protein was increased by 34%. Samples of heel skin were taken at the end of the experiment. The extracellular and plasma spaces in the tissue samples were measured using 51Cr-labeled ethylenediaminetetraacetic acid and 125I-labeled human serum albumin, respectively. The protein spaces were calculated from measurements of endogenous albumin and IgG concentrations using rocket electroimmunoassay. After bradykinin, the interstitial volume was 28% greater than control, whereas the extravascular masses of albumin and IgG were twice as great as the control values. Based on lymph concentration, both proteins distributed in 50% of the interstitial volume during control. Following bradykinin, both proteins distributed in a greater fraction of the interstitium. However, the excluded volume, equal to 0.9 ml/g dry wt, was not altered after bradykinin. This may indicate an increase in free-fluid channels with no hydration of the interstitial gel matrix.

Animals↗