Mortality In Surgical Patients Research Articles

PREOPERATIVE ASSESSMENT OF COMMON DISEASES IN THE OUTPATIENT SETTING

Perioperative myocardial infarction (MI) is a major source of morbidity and mortality in surgical patients. Each year an estimated 50,000 patients in the United States experience perioperative and mortality exceeds 20,000 annually.44 The average cost to hospitals is estimated in one source to be $12,000 per ~atient.4~ The risk of perioperative MI is greatly increased in patients with previous infarction within 6 months of 69 and elective outpatient surgery should be postponed in such patients. In patients with previous MI for whom surgery cannot be postponed an appropriate number of weeks, or in patients without prior MI who have coronary artery disease (CAD) or stable angina, the use of preoperative testing can identify which patients are at increased risk of perioperative cardiac ischemia. For patients with recent MI in whom surgery is not completely elective but not truly emergent (e.g., a patient with a resectable malignancy) evaluation of left ventricular function and exercise tolerance may identify patients with relatively small risks. The nature of the surgery to be undertaken has considerable influence over the risks of surgery in patients with CAD. Backer et a1 found that ophthalmologic surgery under local anesthesia was safe, even in patients with recent ML4 The number of patients in the study who underwent ophthalmologic surgery under general anesthesia was small, but they also did well. Transurethral resection of the prostate appears to carry low risk, even in patients with serious heart disease,-*' and many authors suggest that the risks of peripheral extremity procedures is also l0w.7~ Vascular surgery is associated with increased risk.60 The identification of patients with preoperative myocardial ischemia is an important step in identifying patients at increased anesthetic and surgical risk. Slogoff and Keatsm demonstrated that perioperative myocardial ischemia is associated with perioperative MI. Preoperative testing that defines patients at

Clostridium difficile colitis in the critically ill.

Morbidity and treatment of Clostridium difficile colitis (CDC) continue to be controversial. Some claim minimum morbidity, which may be a function of differences in patient population and/or bacterial virulence. To evaluate the effect of CDC in the critically ill, we retrospectively reviewed the records of 59 intensive care unit patients with CDC who were diagnosed by fecal toxin assays or clinical evidence of pseudomembranous colitis from January 1991 to October 1994. Symptoms, signs, antibiotic regimens, diagnostic tests, Acute Physiology and Chronic Health Evaluation II (APACHE II) scores, morbidity, and mortality were analyzed, and results of surgical treatment were compared with the literature. Mean age was 66.4 (17-95) years, with a male to female ratio of 1.8:1. First treatment was metronidazole by mouth in 15 patients (25.4 percent), vancomycin by mouth in 30 patients (50.8 percent), sequential by mouth vancomycin/metronidazole in 3 patients (5.1 percent), and intravenous metronidazole in 5 patients (8.5 percent). Six patients had no medical therapy before surgery or discharge. Ten patients (17 percent) had recurrence and 12 (20.3 percent) required surgery for progressive toxicity or peritonitis. Of three patients who were initially treated by diverting stomas, one died and two required total colectomy (TAC). Two underwent partial resection (1 that was nearly a total colectomy), and seven others had a TAC. Surgical patients had worse mean APACHE II scores at diagnosis (24.4 vs. 19.9; P < 0.001). Thirty-day mortality in surgical patients was 41.7 vs. 14.7 percent in medical patients (P < 0.5). Twenty percent of critically ill patients with CDC required operation. TAC and diversion appeared to be more effective surgical treatments than diversion alone.

The importance of volume in colorectal cancer surgery

Lothian and Borders Health Boards. Lothian and Borders large bowel cancer project: immediate outcome after surgery. Br J Surg 1995; 82: 888-90. 5. Hermanek P, Wiebeit H, Staimmer D, Riedl S, and the German Study Group for Colorectal Cancer. Prognostic factors of rectal cancer---experience of the German multicentre study SGCRC. Tumori (in press). 6. Junor E J, Hole D J, Gillis CR. Management of ovarian cancer: referral to a multidisciplinary team matter. Br J Cancer 1994; 70: 363-70. 7. Kehoe S, Powell J, Wilson S, Woodman C. The influence of the operating surgeon's specialisation on patient survival in ovarian carcinoma. Br J Cancer 1994; 70: 1014--7. 8. Gillis CR, Hole DJ. Survival outcome of care by specialist surgeons in breast cancer: a study of 3786 patients in the West of Scotland. Br Med J 1996; 312: 145-8. 9. An expert advisory group on cancer to the Chief Medical Officers of England and Wales. Consultative Document: A Policy Framework for Commissioning Cancer Services, 1994. 10. Matthews HR, Powell DJ, McConkey CC. Effects of stirgical experience ofthe results of resection for oesophageal carcinoma. Br J Surg 1986; 73: 621-3. 11. Edge SB, Schmieg RE, Rosenlof KL, Wilhelm MC. Pancreatic cancer resection outcome in American University Centres in 1989-1990. Cancer 1993; 71: 3502-9. 12. Sainsbury R, Haward RA, Rider L, Johnson C, Round C. Influence of clinician workload and patterns of treatment on survival from breast cancer. Lancet 1995;.345: 1265-70. 13. Kelly RV, Hellinger FJ. Physician and hospital factors associated with mortality of surgical patients. Med Care 1987; 25: 489-503. 14. Munoz E, Mulloy A, Goldstein J, Tenebaum N, Wise I. Costs, quality and the volume of surgical oncology procedures. Arch Surg 1990; 125: 360-3.

Strategies for Pain Management in Traumatic Thoracic Injuries

Tissue damage, such as that caused by traumatic injury, is associated with the sensations and responses characterized initially as acute pain. It is known that unrelieved pain contributes to morbidity and mortality in surgical patients. Is pain contributing to morbidity and mortality in critically injured patients as well? Nurses are in a critical position to assess and manage pain. They must be familiar with the wide variety of available pain management techniques and be prepared to advocate their use.

Prognostic indicators in fungemia of the surgical patient.

The objective of this study is to identify prognostic factors affecting mortality in surgical patients with culture-proved fungemia and to examine how amphotericin B affects mortality after controlling for these factors. The study is based on a retrospective logistic regression analysis of general surgical patients with blood cultures positive for fungi. We analyzed the patients' ages; whether they received triple antibiotics, had diabetes, had malignant neoplasia, received steroids, had concomitant bacteremia, or took antibiotics for greater than 7 days; and total dose of amphotericin B. The study was carried out at a university-based county hospital. Analysis of microbiology records for blood cultures that were positive for fungi from November 1987 to January 1992 revealed 63 general surgical patients. Patients with burns and those undergoing organ transplantation were excluded. Forty charts were complete and available for review. Death was the outcome variable studied. Stepwise logistic regression analysis of death revealed age to be a risk factor for mortality. Treatment with at least 210 mg of amphotericin B was associated with relative risk of death of 0.055. Amphotericin B is effective even at low doses at decreasing the mortality in surgical patients with fungemia. On the other hand, increasing age is associated with an increased risk of mortality. Found not to be associated were concomitant bacteremia, concurrent triple antibiotic therapy, malignant neoplasia, and steroid use.

Does Peri-Operatively Increasing Oxygen Delivery Reduce Mortality in Surgical Patients?

Does Peri-Operatively Increasing Oxygen Delivery Reduce Mortality in Surgical Patients?

Microbial Pathogenicity and Host Defense Mechanisms - Crucial Parameters of Posttraumatic Infections

Posttraumatic and postoperative infections which may be either localized or turn into sepsis are a major cause of morbidity and mortality in surgical patients. They derive from the imbalance between microbial pathogenicity factors and the host defense system. The virulence mechanisms include adhesion, chemotaxis, invasion, resistance, and production of toxins. In addition, local and/or systemic immune functions in these patients are altered. Unspecific as well as specific cellular and humoral defense mechanisms are affected. The interaction of defined microbial pathogenicity factors with immune effector cells results in the activation of a variety of inflammatory mediators; they are a prerequisite for protective immunity but also induce local or systemic damage in the host when they occur in excessive amounts or when their metabolism is inadequately controlled. The analysis of the pathophysiological events during infection in surgical patients by taking advantage of modern molecular and cell biological methods may contribute to the development of novel therapeutic strategies.

Effects of Biliary Obstruction on Hepatic Clearance of Bacteria

High surgical mortality in patients with obstructive jaundice and sepsis have been attributed to reticuloendothelial system (RES) depression. The purpose of this study was to clarify the effects of mechanical biliary obstruction on RES clearance of pathogenic bacteria by comparing the phagocytic index (K) with the directly measured hepatic uptake of indium 111-labeled bacteria injected into the portal vein of normal dogs and dogs with partial (PBO) or complete biliary obstruction (CBO). No significant difference was observed between the K in normal dogs (0.19 +/- 0.08; n = 6) and that in dogs with PBO (0.24 +/- 0.06; n = 5) or CBO (0.21 +/- 0.03; n = 4). There was no significant difference in uptake of radiolabel by the liver among the three groups of dogs. In our model, biliary obstruction had no effect on hepatic RES function and may not represent a significant determinant of mortality in patients with obstructive jaundice.

Postoperative pneumonia and urinary-tract infection: epidemiology and prevention

Hospital-acquired pneumonias and urinary-tract infections are important causes of morbidity and mortality in surgical patients, and a great deal of effort has been expended on infection control strategies to prevent their occurrence. Prophylactic antibiotics, used either systemically or topically, are not routinely recommended for the prevention of either of these infections. The beneficial effects of these agents are transient, and they are often in association with the acquisition of colonization or infection with resistant bacteria. New approaches for infection control, not involving antibiotic agents, are being developed to lower the infection rates of both hospital-acquired pneumonias and urinary-tract infections to an irreducible minimum.

What Causes In-Hospital Mortality of Surgical Patients with Cancer of the Stomach?

To learn more about causes of in-hospital mortality, we analyzed data on 1423 patients who underwent any of 6 surgical procedures at 22 departments of surgery between 1982 and 1984. Patients with cancers of the whole stomach had the highest mortality rate, and those with cancers of the middle third the lowest. The deeper the tumor invasion through the stomach wall, the higher the mortality. Total gastrectomy was performed most frequently. In-hospital mortality for total gastrectomy was lower (10.4%) than for gastroenterostomy (23.3%), proximal resection (18.3%), or other procedures for palliation (16.2%) and as high as explorative laparotomy (9.6%). Purely surgical complications were the cause of death in 5.6–20.2% of those who died in the hospital, whereas cardiac, pulmonary, or kidney complication caused 51.8% of the deaths during hospital stay.

In-Hospital Mortality of Surgical Patients

Several public and private groups have set minimum procedure-specific volume standards. Such standards reflect concerns about hospital quality and cost. In-hospital mortality rates are often taken as one measure of quality. To learn about variations in in-hospital mortality rates, we analyzed data on patients who underwent any of seven surgical procedures from a national cohort of 521 hospitals observed continuously between 1972 and 1981. On the average, mortality rates fell as the number of procedures performed annually at the hospital rose. Volumes at which mortality rates reached minimum levels were far higher than actual volumes achieved by the vast majority of hospitals. However, knowledge of hospital volumes left the major part of variation among hospitals' procedure-specific mortality rates unexplained. Many hospitals with low volumes of certain procedures had no associated deaths. Hospitals experienced appreciable year-to-year variation in mortality even though mortality rates fell with the number of years the procedure was performed at the hospital. Correlations among mortality rates for the procedures were low, suggesting that variation in rates is procedure rather than hospital specific. State rate-setting programs had no effect on mortality rates associated with the procedures analyzed. For several reasons, we conclude that an adequate statistical basis for setting minimum volume standards does not presently exist.

Physician and hospital factors associated with mortality of surgical patients.

Recent studies have found an inverse relationship between hospital-specific mortality rates for selected conditions and the number of patients hospitalized with these conditions. These studies have not examined whether this inverse relationship is a result primarily of the nature and volume of services provided to patients by individual physicians or whether it reflects special characteristics of high-volume hospitals. This study examines these issues, using data that link characteristics of primary surgeons to the discharge abstract records of patients. The study analyzes variation in hospital mortality associated with: the total volume of specific surgical procedures performed in the hospital, the volume of these procedures performed by the patient's primary surgeon, physician board certification, and other factors including patient severity of illness, patient age, hospital control, teaching status, size, and location. The findings confirm the inverse relationship found in other studies between patient mortality and the total volume of specific surgical procedures performed in the hospital. Physician board certification and hospital's medical school affiliation also are found to be associated with lower patient mortality rates. However, there is no statistical relationship between the volume of services provided by individual surgeons and outcome, suggesting that the volume-outcome relationship reflects hospital rather than physician characteristics.

Practical problems in assessing risk for coronary artery bypass grafting

In order to put results of a surgical program in proper prospective, risk factors for the population being treated should be carefully assessed. This paper discusses the practical problems involved in determining the risk of surgical mortality for patients undergoing isolated coronary artery bypass grafting. A risk equation developed by the Collaborative Study in Coronary Artery Bypass was applied to a veterans hospital population. A simplified method of determining left ventricular function from clinical angiography reports was found to be a reasonable substitute for the more complex left ventricular scoring system used by the collaborative study. Results showed the veterans group to be at increased risk, primarily due to an older average age and higher incidence of left ventricular dysfunction.

Assessment of Risk Factors and Surgical Outcome

Patients with known cardiac disease who face operative procedures are usually more concerned than other patients because they perceive themselves to be at greater risk. By reviewing several studies of preoperative risk factors, the author attempts to find which factors imply significant risk of mortality in surgical patients with cardiac disease.

Surgical management of prosthetic valve endocarditis

Operative mortality in patients with prosthetic valve endocarditis (PVE), who already have severe hemodynamic failure, is extremely high (35% to 84%). Over a period of 10 years, between 1972 and 1981, fourteen consecutive urgent operations were performed for PVE in 12 patients. On thirteen occasions the patients were in severe hemodynamic failure (NYHA Functional Class IV), and five of them had early PVE (within 60 days of previous operation). In all patients at least two of the other recognized risk factors, such as presence of non-streptococcal organisms, detachment of the prosthesis, and myocardial invasion, were present. All of the patients but one were operated upon within 48 hours of their hemodynamic deterioration, and there was one postoperative death (operative mortality 7%). Our results indicate that an acceptable surgical mortality in patients with intractable heart failure due to early and late PVE can be achieved by prompt surgical intervention despite the presence of multiple risk factors.

Segmental study of the terminal coronary vessels in coarctation of the aorta: A natural model for study of the effect of coronary hypertension on human coronary circulation

An electron microscopic study of the coronary terminal circulation (starting with the small coronary arteries) was carried out on small pieces of myocardium operatively resected from the left ventricle in 11 patients with coarctation of the aorta. The patients were 4 to 20 years of age. Structural modifications were found in the small coronary arteries and arterioles. Two patterns of morphologic alterations were noted in these small resistance vessels. In the first pattern, seen in most of the children, the components of the arterial wall were still distinguishable, and well represented portions of smooth muscle layers were visualized together with muscle cells showing signs of degeneration and more or less widespread collagenous islets. The second pattern, seen in young adults, was characterized by a total collagenous transformation of the arterial wall. In contrast, the smaller microvessels (precapillary sphincters, metarterioles and capillaries) appeared free of pathologic change. It is postulated that the precapillary sphincters play a special protecting and regulating role in the coronary microcirculation in such cases with elevated coronary pressure. It is suggested that surgery should be performed at an early age to prevent further development of structural changes in the microvessels. The microcirculatory damage may contribute to the increased surgical mortality in patients with coarctation of the aorta operated on at a later age. These findings should trigger further research on the small coronary vessels in systemic hypertension.

Surgery in active infective endocarditis.

Controversy persists concerning the role of early surgical intervention in severe infective endocarditis (IE). We therefore reviewed 163 episodes of well-documented IE in which 32 cardiac operations were performed during the active phase of IE. Congestive heart failure (CHF) was the principal indication for surgery in 88% (28/32); systemic emboli, 1/32; and persisting sepsis, 3/32. Staphylococcus and enterococcus were the most common infecting organisms in the operative group (44% and 16% respectively). Surgical mortality (11/32,37%) did not differ (p greater than 0.05) from medical mortality (26/131,20%). All 11 operative deaths occurred in patients moribund prior to surgery, including three with preoperative cardiac arrest. Surgical patients undergoing preoperative cardiac catheterization demonstrated marked CHF: a mean left ventricular end-diastolic pressure of 25.3 mm Hg. The mean cardiac index in 8/11 surgical deaths was lower (p less than 0.05) vs surgical survivors: 2.21/min/m2 vs. 3.21/min/m2. Postoperative complications were rare in the 21 surgical survivors. There were no episodes of continued infection, prosthetic dehiscence, or advanced heart block; only one paravalvular leak; and one systemic embolus. These findings emphasize the high medical and surgical mortality in patients with IE, suggest that delayed operative intervention may be a major causative factor resulting in a high surgical mortality, and justify an aggressive surgical approach in patients with valve dysfunction and heart failure. These data indicate that survivors of surgical intervention during active IE have eradication of infection and few postoperative complications.

Selective Intra-arterial Vasopressin

A retrospective analysis of results obtained over a three year period in 66 patients receiving selective intra-arterial vasopressin (SIAV) for control of 69 episodes of massive gastrointestinal bleeding was presented. SIAV was used when there was a failure of conventional medical therapy and the patient's pathology and/or complicating medical conditions necessitated an attempt at controlling an emergent condition by nonoperative means. Hemmorrhage was completely controlled in 43% of variceal bleeds, 67% of hemorrhage gastritis, 45% of bleeding ulcers, and in 62% of colonic sources. The incidence of rebleeding following initial control was 16%. The surgical mortality for patients who were initial failures of SIAV was 50%. Patients undergoing elective surgery after complete control by SIAV had an 8% mortality. There were five catheter related complications. Minor complications occurred in 41% of patients, but required no treatment. Major complications occurred in 40% of cirrhotic and 21% of noncirrhotic bleeding episodes; and were a contributing factor in five cirrhotic deaths and three noncirrhotic deaths. In critically ill patients in the setting of an Intensive Care Unit, selective intra-arterial vasopressin appears: 1) to be an effective means of controlling certain types of gastrointestinal hemorrhage; 2) to provide an opportunity for an increase in survival rate.

Criteria for Operability and Reduction of Surgical Mortality in Patients with Severe Left Ventricular Ischemia and Dysfunction

A series of 188 patients who were operated on for left ventricular ischemia and dysfunction is presented. Angina was a prominent symptom in all patients, and a history of congestive heart failure could be elicited in 20%. Mean ejection fraction for the series was 0.35, with 67% having an ejection fraction of 0.35 or less and 24%, 0.20 or less. Complete revascularization was accomplished whenever possible; more than 70% of the patients had triple-vessel disease, and single bypass was performed infrequently (5%). Factors thought to be important in achieving a low operative mortality (2.1%) were: precise prebypass monitoring, particularly with the V5 precordial lead; maintaining a low rate-pressure product (<12,000) prior to bypass; myocardial preservation with cold hyperkalemic or hyperkalemic-hyperosmolar solution; and careful titration of inotropic and vasodilator drugs. Inotropic drugs and intraaortic balloon pumping were used frequently in this series. The late mortality was 4.3%. Angina was completely relieved or improved in 94% of the patients. Those having a history of congestive heart failure had an increased late mortality rate, four times that of the entire series.

Echocardiography in ischemic heart disease

Echocardiographic findings in patients with ischemic heart disease are described; their correlations with clinical, hemodynamic and angiographic data are presented and discussed. Regional abnormalities of left ventricular wall motion and/or thickening during systole are detected in 84 per cent of patients with acute myocardial infarction and in a high percentage of patients with ≥75 per cent narrowing of a major coronary artery. These abnormalities may occur with stress and may be reversible. Left ventricular wall thinning during systole indicates acute ischemia or infarction and thin, dense myocardial echoes indicate scar. Echocardiographic evidence of left ventricular dysfunction is useful in predicting heart failure and mortality in patients with acute myocardial infarction and in predicting surgical mortality for patients undergoing aneurysmectomy and/or coronary artery bypass surgery. Echocardiography has not proved useful in determining graft patency following coronary artery bypass surgery. Technical difficulties and limitations of echocardiography in patients with coronary artery disease are discussed.