Acute acalculous cholecystitis: incidence, risk factors, diagnosis, and outcome.

The objective of this study was to review the incidence, risk factors, methods of diagnosis, and outcome of acute acalculous cholecystitis (AAC) and to identify the sensitivity and limitations of current radiographic modalities used to establish the diagnosis. Our study was a retrospective chart review in a tertiary-care university hospital. Over a 53-month period, 27 cases of AAC (17 males, 10 females; mean age 50 years; mean Acute Physiology and Chronic Health Evaluation II score, 17) were encountered. Of these, 14 (52%) occurred in critically ill patients and 17 (63%) in patients recovering from non-biliary tract operations. AAC occurred in 0.19 per cent of surgical intensive care unit admissions and accounted for 14 per cent (27 of 188) of all cases of acute cholecystitis. Presenting symptoms and laboratory values were nonspecific. Twenty patients had radiographic studies before surgery. Among the various radiological studies used for AAC, morphine cholescintigraphy had the highest sensitivity (9 of 10; 90%), followed by computed tomography (8 of 12; 67%) and ultrasonography (2 of 7; 29%). Ten of the 20 patients had more than one study done preoperatively. All 27 patients had an open cholecystectomy. AAC was associated with a high incidence of gangrene (17 of 27 cases; 63%), perforation (4 of 27; 15%), and abscess (1 of 27; 4%). The mortality rate was 41 per cent (11 of 27). We conclude that AAC is a rare, but potentially lethal, disease occurring in critically ill patients and those recovering from non-biliary tract operations. The clinical presentation is nonspecific, and significant delays in diagnosis result in a high incidence of gangrene, perforation, abscess, and death. To improve outcome, a high index of suspicion with early radiographic evaluation, often employing multiple studies, is necessary. An algorithm for the evaluation of patients for suspected AAC is proposed.

Optimizing arthroscopic knots using braided or monofilament suture.

Surgeons need to know how the material properties of a suture affect the security of a surgical knot. The purpose of this study was to compare the security of some clinically important arthroscopic knots when tied using a braided multifilament suture and to draw comparisons with results of similar knots tied with monofilament suture. Permanent braided polyester suture was used to test 10 knot configurations. Eight of the knots included (1) two types of initial cinching knots followed by (2) one of four combinations of half-hitches. We also tested the taut-line hitch locked with half-hitches and the original Revo knot. Each knot was subjected to cyclic loading followed by an ultimate load to failure. Clinical failure was defined as the maximum force that resulted in 3 mm of loop displacement. Force versus displacement data were obtained, and the maximal loop holding capacities were compared statistically. The Duncan loop with switched-post half-hitches and the Revo knot (Linvatec, Largo, FL) showed the highest knot-holding capacities (mean, 87N and 92N, respectively) when compared with all other configurations (P < .0001) for braided suture. A similar knot-holding capacity was described for monofilament suture using the Duncan loop locked with switched-post, reversed-direction half-hitches (mean, 81 N). All knots without post switching slipped completely at significantly lower loads than knots with post switching (monofilament, P < .001; braided, P < .0001). When compared with results of knots tied with monofilament suture, the braided switched-post configurations had smaller cyclic displacements (braided, 0.7 mm; monofilament, 1.7 mm). Although the Revo knot showed good strength for braided suture, it was significantly weaker than other configurations when tied with monofilament suture. Therefore, it is important to test the knot strength for a given suture material before applying it clinically.

Preoperative intensive care unit admission and hemodynamic monitoring in patients scheduled for major elective noncardiac surgery: a retrospective review of 95 patients.

OBJECTIVE: To review experience with preoperative intensive care unit (ICU) admission and hemodynamic monitoring to determine which patients benefited and how. DESIGN: Retrospective review over 32-month period (1991 to 1994). SETTING: Surgical ICU of a university teaching hospital. PARTICIPANTS: Ninety-five patients admitted to the surgical ICU before a major elective noncardiac, nonthoracic surgical procedure. INTERVENTIONS: All patients underwent hemodynamic monitoring with a pulmonary artery catheter (PAC). Interventions were made at the discretion of the ICU attending and attending surgeon, based on a general algorithm. Patients were categorized based on history or hemodynamics. The historic classification was as follows: group I, patients with cardiac disease documented by history and cardiac imaging, n = 37; group II, patients with cardiac disease documented by history, but not cardiac imaging, n = 24; group III, patients without documented cardiac disease, but with other significant medical problems, n = 34. Hemodynamic classification considered patients to have subnormal parameters if the cardiac index was < 2.5 L/min/m2, the mixed venous oxygen saturation was < 65%, or the oxygen delivery index was < 350 mL/min/m2 (n = 45), and normal parameters if greater than these (n = 50). MAIN RESULTS: There were no differences in APACHE II scores. Group I patients had greater Goldman Cardiac Risk Indices than group III patients (7.4 +/- 4.8 v 5.0 +/- 3.0). Patients in group I had a significantly greater incidence of subnormal initial hemodynamic values (63%) than patients in group II (47%) or group III (32%). The incidence of postoperative cardiovascular complications among groups was not different. Fifty patients (52%) had normal hemodynamics initially; two (4%) developed postoperative cardiovascular complications compared with 10 patients (22%) of the 45 with subnormal initial hemodynamic values. Of these 45 patients, 24 (52%) had their hemodynamic parameters corrected preoperatively with crystalloids, packed red blood cells, inotropes, and/or afterload reduction. Two of these 24 patients (8%) experienced postoperative cardiovascular complications, compared with 8 of the remaining 21 patients who had no attempt to normalize their hemodynamic values preoperatively other than maintaining a normal pulmonary artery occlusion pressure. CONCLUSIONS: Patients who had normal initial preoperative hemodynamic parameters or abnormal initial parameters that were normalized preoperatively experienced significantly fewer perioperative cardiovascular complications than those with abnormal initial values that were not normalized preoperatively. These results suggest that there may be benefit to the practice of preoperative ICU admission, hemodynamic monitoring with a PAC, and "optimization" of cardiac function in selected patients undergoing major elective noncardiac surgery. Further studies are needed to better delineate the most appropriate patient populations and effective therapeutic protocol.

A prospective randomized trial of preoperative "optimization" of cardiac function in patients undergoing elective peripheral vascular surgery.

BACKGROUND: Previous investigations have suggested that preoperative invasive hemodynamic monitoring with "optimization" of cardiovascular function may favorably affect the outcome among patients undergoing peripheral vascular surgery. The purpose of this study was to evaluate the effect of preoperative optimization of hemodynamic parameters on outcome in patients undergoing aortic reconstruction (AR) or limb salvage procedures (LSP) in a randomized, prospective clinical trial. METHODS: All 72 patients who consented to participate in this study were admitted to the intensive care unit at least 12 hours before operation for placement of a pulmonary artery catheter (PAC). Patients who were randomized to the treatment group (n = 32) were "optimized" by adjusting their hemoglobin concentration, oxygen saturation (SaO2), cardiac output, or afterload until the mixed venous O2 saturation (SvO2) was at least 65%. The control group (n = 40) underwent placement of a PAC and had oxygen transport parameters measured without any attempt to optimize SvO2. RESULTS: There were no significant differences between the treatment and control groups with respect to age, gender, type of operation, initial Acute Physiology and Chronic Health Evaluation (APACHE) II score, SvO2, pulmonary artery occlusion pressure, or cardiac index. All treatment patients achieved an SvO2 of at least 65% before operation. Comparing the treatment and control groups, postoperative cardiovascular complications occurred in 25% versus 27%, intraoperative complications in 28% versus 20%, and death in 9% versus 5%, respectively. None of these differences was statistically significant as a whole or within the subgroups undergoing AR or LSP. CONCLUSIONS: These data suggest that preoperative optimization of cardiovascular function by using achievement of SvO2 above 65% as the end point does not result in any reduction of intraoperative or perioperative cardiac complications in patients undergoing PVS. Further studies with alternative assessments and manipulation of different cardiopulmonary parameters may yield additional information.

Patient self-assessment of health status and function in glenohumeral degenerative joint disease.

One hundred three consecutive patients with primary glenohumeral degenerative joint disease completed standard questionnaires regarding their general health status (Short Form-36) and the function of their shoulder (Simple Shoulder Test). These patients' self-assessed health status indicated overall bodily pain, physical functioning, and physical role fulfillment scores that were significantly below those of population-based control groups. Self-assessed shoulder functions were likewise consistently below those of patients with normal shoulders. These deficits clearly indicated the problems that the patients desired to have resolved by treatment. The use of self-assessment questionnaires to routinely characterize patients with shoulder conditions is practical in the context of a busy practice. These data enable surgeons to understand the condition from the patient's perspective. This understanding should be central to the planning of treatment and to the evaluation of treatment effectiveness.

Repair of the rotator cuff. A comparison of results in two populations of patients.

One hundred and seven shoulders of 103 consecutive patients were evaluated after primary repair of the rotator cuff. Twenty-four patients were receiving Workers' Compensation, and the other seventy-nine were not. Preoperative and postoperative evaluation of both groups included subjective assessment of pain, function, and patient satisfaction as well as objective assessment of the strength and active range of motion of the shoulder. The shoulder-rating scale of the University of California at Los Angeles was used to determine over-all success rates. The duration of follow-up ranged from twenty-four to sixty-eight months (mean, forty-five months). The two groups were comparable with regard to the age and sex of the patients, the size of the tear of the rotator cuff, and the preoperative strength, pain, and active range of motion of the shoulder. Over-all, a successful result was achieved in eighty-nine of the 107 shoulders. Of the twenty-four shoulders of patients who were receiving Workers' Compensation, thirteen (54 per cent) were rated good or excellent, compared with seventy-six (92 per cent) of the eighty-three shoulders of patients who were not receiving Workers' Compensation. Ten (42 per cent) of the twenty-four patients who were receiving Workers' Compensation returned to full activity, compared with seventy-four (94 per cent) of the seventy-nine patients who were not.

Obturator hernia needs a laparotomy, not a diagnosis.

The obturator hernia is rare, accounting for only 0.05% of all hernias and 0.2% of all small-bowel obstructions requiring laparotomy at our institution. Typically, there is a delay in diagnosis and surgical intervention, despite the presence of a bowel obstruction. A laparotomy is needed, not a preoperative diagnosis.

First place winner of the Conrad Jobst Award in the gold medal paper competition. Nitric oxide synthase inhibitors N-monomethylarginine and aminoguanidine prevent the progressive and severe hypotension associated with a rat model of pancreatitis.

The objective of this study was to determine whether the observed vascular collapse and other pathologic features of severe pancreatitis may be related to the induction of nitric oxide synthase (NOS). The rat model of pancreatitis reported by Schmidt et al. was employed. Rats in the experimental groups received pretreatment with known NOS inhibitors, N-Monomethylarginine (NMMA) or Aminoguanidine (AG). Controls included sham-operated rats without pancreatic insult and a diseased control group which received pretreatment with normal saline (NS). Arterial blood pressure was continuously recorded with a femoral arterial catheter connected to a transducer and monitor. Fluid resuscitation for hypotension followed a strict protocol with the administration of 5.0 cc NS for sustained decreases in systolic blood pressure (SBP) below 90 mm Hg at 5-minute intervals. Laboratory parameters and histopathology confirmed the induction of pancreatitis, with 6 to 15-fold increases in serum amylase levels and an average of approximately 20% decrease in serum ionized Ca++ levels. Immunohistochemical studies of the pancreas revealed that pancreatic insult resulted in the induction of NOS. Rats in the saline control group (n = 5) became hypotensive (SBP less than 90 mm Hg) between 3 and 4 hours post pancreatic insult and required an average of 110.0 cc (3-4 x blood volume) of NS fluid resuscitation. Rats which were not resuscitated (n = 5) did not survive.(ABSTRACT TRUNCATED AT 250 WORDS)

The morbidity and mortality of rib fractures.

The incidence of rib fractures secondary to trauma has not been clearly reported. Of the 7147 patients seen by our trauma service from January 1987 to June 1992, 711 (10%) had rib fractures. Among the patients with rib fractures, 84 (12%) died, 670 (94%) had associated injuries, 274 (32%) had a hemothorax or pneumothorax, and 187 (26%) had a lung contusion. Fifty-five percent of the patients required an immediate operation or admission to the intensive care unit. Thirty-five percent of the patients required discharge to an extended care facility and 35% developed a pulmonary complication. We conclude that rib fractures are a marker of severe injury in which (1) 12% will die because of their injuries, (2) more than 90% will have associated injuries, (3) one half will require operative and ICU care, (4) one third will develop pulmonary complications, and (5) one third will require discharge to an extended care facility.

Pancreatitis in childhood. Experience with 49 patients.

Pancreatitis in children is not common but can be associated with severe morbidity rates. We have treated 49 children with pancreatitis over the past 12 years ranging in age from 1 month to 18 years. One third of the patients had biliary tract disease as an etiology, with nearly half of these being related to underlying hematologic disease, usually sickle cell anemia. Another third of the pancreatitis was due to trauma, and one third of these were related to child abuse. Other etiologies were systemic disease (6 patients), congenital anomalies (8 patients), and idiopathic (3 cases). Eighty-two per cent of the patients presented with abdominal pain, but four children, all less than 4 years old, presented with an abdominal mass. Twenty-nine patients required 33 operations for pancreatitis. Fifteen of the 16 patients with biliary tract disease and all patients with congenital anomalies required operation. Six of the 16 patients with trauma required operation and none of those with systemic disease. As in adults ultrasonographic examination and CT scan are most important in the diagnosis; medical treatment consists of intravenous (I.V.) fluids, nasogastric suction, and total parenteral nutrition (TPN), and risk factors can help predict the severity of the disease while amylase alone is not related to severity. Different from adults, in children an etiology can usually be determined. The common etiologies, biliary tract disease, trauma, and congenital anomalies frequently require operation.

Diagnostic and treatment problems in renal injuries.

The case records of 112 patients with 116 renal injuries seen at Detroit Receiving Hospital (July 1980 to June 1985) were reviewed. Eighty-three (74%) of the injuries were caused by gunshot wounds, 18 (16%) by stab wounds, and 11 (10%) by blunt trauma. Of 102 patients who had a urinalysis (U/A) in the Emergency Department (ED), 12 had a normal U/A. Five of these 12 patients had severe renal pedicle injuries. Of 75 excretory urograms (IVPs) performed preoperatively, 21 (28%) were normal including seven in patients with major renal injuries requiring surgical treatment. The incidence of shock was 38 per cent in patients with injuries not requiring renal explorations, 69 per cent in patients with renal parenchymal injuries requiring surgery, and 93 per cent in patients with pedicle injuries requiring repair or nephrectomy. Although it is generally believed that traumatic perirenal hematomas should not be explored, there was an increased incidence of complications with this approach in this series. Of 65 stable renal injuries treated conservatively (without exploration of the renal parenchyma), there were nine (14%) complications including three reoperation for missed injuries and three perinephric abscesses. In 46 injuries that were explored (38 for bleeding and eight without bleeding), there were only two complications (5%), including a perinephric abscess.

Experimental allergic neuritis-like disease in rabbits after injection with influenza vaccines mixed with gangliosides and adjuvants.

An experimental allergic neuritis-like disease was induced in rabbits 3 to 8 weeks after injection with large doses of influenza vaccines mixed with gangliosides, cholesterol, and Freund complete adjuvant. The inclusion of gangliosides was essential to induce the experimental allergic neuritis-like disease. In trials with six different lots of vaccine, both swine influenza and non-swine influenza vaccines produced by four different manufacturers induced experimental allergic neuritis-like disease in 26 of 43 inoculated rabbits.

Characterization of antibodies to orthopoxviruses in human sera by radioimmunoassay.

Serological surveillance of suspected orthopoxvirus infections in man is important for confirming the success of the worldwide smallpox eradication programme. An adsorption radioimmunoassay (RIA) was used to differentiate sera from patients who were naturally infected with human monkeypox or variola virus, and individuals who were immunized with vaccinia virus. The antisera were adsorbed with uninfected chicken chorioallantoic membrane (CAM) and vaccinia-infected CAM before reacting in RIA with vaccinia, monkeypox, and variola antigens. Each serum group showed characteristic patterns of residual antibody activity which made it possible to identify antibody specificities.When 45 human sera were tested by this method, 71% were identified as having vaccinia, variola, or monkeypox adsorption characteristics, while the remaining 29% could not be identified. Of the identified sera, 9 were characteristic of vaccinia, 8 of variola, and 15 of monkeypox. Six of the 15 monkeypox sera were virologically confirmed monkeypox infections, 6 were suspected monkeypox infections but were not virologically confirmed, and 3 were of unknown aetiology.The adsorption RIA provides a method of identifying serologically the poxvirus responsible for infection long after the acute phase of illness.

A study of the specificities of sequential antisera to variola and monkeypox viruses by radioimmunoassay.

The specificities of antisera during development of the humoral antibody response to poxvirus antigens were examined in monkeys injected with chimp-9 whitepox virus or monkeypox virus. Sera were obtained from 3 African green (vervet) monkeys inoculated with chimp-9 whitepox virus, 1 rhesus monkey inoculated with monkeypox virus, and 2 rhesus monkeys inoculated with soluble monkeypox viral antigen. The sequentially obtained sera from each animal were adsorbed with uninfected chicken chorioallantoic membranes (CAM) or vaccinia virus-infected CAM. The adsorbed sera were tested by radioimmunoassay to determine the specificity of the residual antibodies to vaccinia, variola, and monkeypox viruses. The adsorbed sera at different stages of the immune response showed increasing specificity with time after inoculation. Generally, antibodies in sera collected earlier than 21-27 days after immunization could not be identified after adsorption, but late sera could be identified unequivocally.

Guillain-Barre syndrome following vaccination in the National Influenza Immunization Program, United States, 1976--1977.

Because of an increase in the number of reports of Guillian-Barre syndrome (GBS) following A/New Jersey influenza vaccination, the National Influenza Immunization Program was suspended December 16, 1976 and nationwide surveillance for GBS was begun. This surveillance uncovered a total of 1098 patients with onset of GBS from October 1, 1976, to January 31, 1977, from all 50 states, District of Columbia, and Puerto Rico. A total of 532 patients had recently received an A/New Jersey influenza vaccination prior to their onset of GBS (vaccinated cases), and 15 patients received a vaccination after their onset of GBS. Five hundred forty-three patients had not been recently vaccinated with A/New Jersey influenza vaccine and the vaccination status for 8 was unknown. Epidemiologic evidence indicated that many cases of GBS were related to vaccination. When compared to the unvaccinated population, the vaccinated population had a significantly elevated attack rate in every adult age group. The estimated attributable risk of vaccine-related GBS in the adult population was just under one case per 100,000 vaccinations. The period of increased risk was concentrated primarily within the 5-week period after vaccination, although it lasted for approximately 9 or 10 weeks.

Solid-phase competitive-binding radioimmunoassay for detecting antibody to the M antigen of histoplasmin.

A radioimmunoassay (RIA) was designed and compared with complement fixation and immunodiffusion tests for their relative ability to detect antibodies in sera of histoplasmosis patients. M antigen, purified from histoplasmin, was fixed to microtiter wells as the solid phase, and specific rabbit 125I-labeled anti-M globulin was the source of indicator antibodies. The optimal concentrations for the competitive-binding assay were 1.6 ng per well for M antigen and 650 ng per well for the 125I-labeled anti-M globulin. A panel of sera from 29 histoplasmosis patients and from patients with other mycoses was screened for RIA activity and in complement fixation and immunodiffusion tests that used histoplasmin and Histoplasma capsulatum yeast-form antigens. The sera of 22 histoplasmosis patients reacted in the RIA, 21 in the complement fixation, and 16 in the immunodiffusion tests. Sera of patients with other mycotic infections did not react in the RIA, with the exception of those of one blastomycosis patient and one candidiasis patient. The RIA could be modified to quantitate M antigen; as little as 125 pg could be detected. The evaluation of this panel of histoplasmosis patients' sera showed that the RIA was about equivalent in sensitivity to the complement fixation test. Some advantages of the RIA over the complement fixation test were that RIA was less prone to cross-reactions and gave better quantitation of low-titered sera. The RIA was a 1-day test, was not hindered by the anti-complementary activity of some sera, and could be modified to quantitate minute amounts of M antigen.