Quantitative blood loss after vaginal delivery: a retrospective analysis of 104 079 measurements at 41 institutions.

BACKGROUND: Peripartum quantitative blood loss (QBL) measurement is recommended over visual estimation. However, QBL measurement after vaginal delivery has been inadequately evaluated. The primary aim of this study was to determine the characteristics of QBL measurements from a large, multicenter cohort of patients having vaginal deliveries. We also determined the incidence of postpartum hemorrhage (PPH) and the relationship between gravimetric QBL from weighed sponges vs. volumetric QBL from liquid drape or suction cannister contents. METHODS: Data were collected from 41 institutions in the United States of America that use an automated QBL device after vaginal delivery as part of routine care. The QBL device tracks cumulative blood loss based on gravimetry and volumetric V-drape assessment, automatically subtracting the dry weights of all blood-containing sponges, towels, pads and other supplies as well as the amniotic fluid volume. RESULTS: Between January 2017 and April 2020, 104 079 QBL values were obtained from patients having vaginal deliveries. Total median [IQR] QBL was 171 [61-362] mL. The PPH incidence, stratified by QBL, was 15.2% (>500 mL), 3.4% (>1000 mL), and 1.0% (>1500 mL). The contribution of QBL from V-drapes was 60.6±26.3% of total QBL. CONCLUSION: Results from this large set of QBL measurements and the PPH incidence provide normative "real-world" clinical care values that can be expected as hospitals transition from estimated blood loss to QBL to assess the blood loss at vaginal delivery.

Repair of postinfarction ventricular septal defect in the elderly. Early and long-term results.

We performed 13 operations on 12 elderly patients with ventricular septal defect (VSD) following myocardial infarction. All patients were older than 65 years (range 66 to 82 years) and six were over 70 years of age. Ten underwent operation, with counterpulsation support, within 3 weeks of development of the VSD. Among eight patients with anteriorly located VSDs, there were four survivors. Among four patients with inferior defects, three survived. Overall hospital survival was 58%. Hospital costs were no greater in the elderly than in younger patients. The seven long-term survivors were followed up for from 10 months to 7.5 years (mean 3.9 years). There was one sudden death at 7.5 years in a previously well man. Of the remaining six patients, five are in New York Heart Association Class I, and one is in Class II. One woman, now 84 years old, lives independently over 2 years after repair. Our experience with respect to management suggests that unless medical therapy results in continued improvement rather than stability alone, hemodynamic deterioration is inevitable, and survival for delayed repair is unlikely. Furthermore, undue delay frequently results in renal failure and severely compromises the chances for survival after repair in the acute state.

Pulmonary artery-bronchial fistula complicating chronic lymphocytic leukemia.

A 52-year-old man with chronic lymphocytic leukemia (CLL) entered the hospital because of repetitive bouts of massive hemoptysis requiring a right pneumonectomy. A bronchus intermedius-pulmonary artery fistula was found and felt to be due to necrosis of a peribronchial lymph node which was infiltrated by chronic lymphocytic leukemia cells. This represents another pulmonary complication in the clinical course of advanced CLL.

Effects of vasoactive drugs on flows through left internal mammary artery and saphenous vein grafts in man.

Vasoactive agents are commonly used in the postcardiopulmonary bypass period to elevate the mean arterial pressure of myocardial revascularization patients. Concern exists that administration of vasoactive agents in this setting may affect flow through saphenous vein and internal mammary artery grafts. Twenty-eight patients were randomly assigned to receive one of the six two-drug combinations of phenylephrine, norepinephrine, and epinephrine. After termination of cardiopulmonary bypass baseline, hemodynamic measurements and electromagnetic flow probe measurements of saphenous vein and internal mammary artery graft flow were made. The first agent was then infused to elevate mean arterial pressure 20 mm Hg. After 5 minutes of stability, hemodynamic and graft flow measurements were repeated. The infusion was terminated, 5 minutes of stability were obtained, and baseline measurements were repeated. The second agent was then infused, and measurements were repeated after a 5-minute stabilization period. Phenylephrine induced a nonsignificant increase in saphenous vein graft flow (68 +/- 31 versus 81 +/- 49 ml/min) and a significant decrease in internal mammary artery graft flow (40 +/- 16 versus 32 +/- 12 ml/min). Norepinephrine induced a significant increase in saphenous vein graft flow (80 +/- 39 versus 97 +/- 39 ml/min) and no significant change in internal mammary artery graft flow (44 +/- 20 versus 45 +/- 20 ml/min). Epinephrine induced a significant increase in both saphenous vein (82 +/- 38 versus 96 +/- 40 ml/min) and internal mammary artery (38 +/- 12 versus 55 +/- 24 ml/min) graft flows. We conclude that administration of vasoactive agents in the postcardiopulmonary bypass period may significantly affect saphenous vein and internal mammary artery graft flows.

Pulmonary microvascular responses to protamine and histamine. Effects of cardiopulmonary bypass.

Total cardiopulmonary bypass with associated reduced pulmonary blood flow causes significant alterations of endothelium-dependent pulmonary microvascular responses after resumption of normal perfusion. To determine if this change in pulmonary vascular reactivity may influence the responses of pulmonary arterioles to protamine and histamine, we examined isolated pulmonary microvessels after cardiopulmonary bypass. Sheep were heparinized, cannulated, and placed on either total bypass without ventilation or partial bypass (70% of baseline pulmonary arterial flow) with continued ventilation. After 90 minutes, sheep were separated from cardiopulmonary bypass and the lungs were perfused normally for 60 minutes. Vessels from noninstrumented sheep were used as controls. Peripheral pulmonary arterioles (90 to 190 microns) were cannulated, pressurized (20 mm Hg) in a no-flow state, and examined with video microscopy. After precontraction of vessels with the thromboxane A2 analog U46619 by 18% to 25% of the baseline diameter, vasoactive agents were applied. Protamine sulfate, histamine, heparin, and the protamine-heparin complex caused significant dose-dependent relaxations of control pulmonary microvessels. These relaxation responses were substantially reduced or converted to contractile responses in endothelium-denuded vessels, which suggests that these relaxations are mediated through endothelium-dependent mechanisms. After partial bypass, responses to protamine and histamine were slightly reduced compared with the respective responses of control vessels, whereas the relaxation to protamine-heparin complex was not significantly altered. After total bypass, relaxation responses to protamine and protamine-heparin complex were markedly reduced, whereas histamine induced contraction of pulmonary microvessels. Endothelium-independent relaxation to sodium nitroprusside was not affected by partial cardiopulmonary bypass and was slightly reduced after total bypass. A reduced direct vascular relaxation response to protamine and increased contractile response to histamine (or other humoral substances released during the systemic administration of protamine sulfate) may contribute to the elevation of pulmonary vascular resistance during infusion of protamine after cardiopulmonary bypass.

Comparison of two transfusion strategies after elective operations for myocardial revascularization.

We performed a prospective, randomized trial of two different strategies for postoperative packed red blood cell replacement in 39 autologous blood donors undergoing elective myocardial revascularization. The "liberal" group received blood to achieve a hematocrit value of 32%, and the "conservative" group received transfusions for a hematocrit value less than 25%. Although the groups had significantly different mean hematocrit values from the fourth postoperative hour (28.7% versus 31.2%) through the fifth postoperative day (28.4% versus 31.3%), there were no significant differences in fluid requirement, hemodynamic parameters, or hospital complications. Significantly fewer units of packed cells were required in the conservatively transfused group (20 units/20 patients) compared with the liberally transfused group (37 units/18 patients) (p = 0.012). Exercise tests were performed on the fifth and sixth postoperative days, with a transfusion being given to the conservative group between tests. Although a significant improvement in exercise endurance occurred in the conservative group receiving a transfusion (p = 0.008), no significant difference in duration or degree of exercise was demonstrated between the two groups on either day. In comparing these two groups of profoundly anemic patients, we identified no adverse consequence associated with the greater degree of hemodilution and could identify no correlation between hematocrit value and exercise capacity. We conclude that although the limits of hemodilution are still poorly defined, postoperative blood transfusion in revascularized patients should be guided by clinical indications and not by specific hematocrit values.

Surgical repair of remediable postinfarction cardiogenic shock in the elderly. Early and long-term results.

The in-hospital mortality associated with acute myocardial infarction rises markedly with advancing age. It is not established whether the elderly may benefit from early surgical repair of postinfarction cardiogenic shock due to ventricular septal defect (VSD), acute severe mitral regurgitation (MR), or left ventricular power failure. Eighteen consecutive patients between the ages of 66 and 79 (mean, 72 years) and in cardiogenic shock underwent surgical repair, most with counterpulsation support, within one week of developing VSD, MR, or left ventricular power failure. Of ten patients with VSD, five (50%) survived. Three of seven patients with MR (43%) and the only patient with power failure survived for an overall survival of 50%. The nine long-term survivors were followed up for six months to five years (mean 31 months) by personal interviews with the patient or referring physician. There was one late death, due to congestive heart failure, ten months after the operation. Of the remaining eight patients, seven are categorized as New York Heart Association class I, and one as class II. These patients have all been able to live and function independently after cardiac operation. The authors conclude that older patients with postinfarction cardiogenic shock may benefit from early operation and that advanced age does not preclude successful surgical outcome. Furthermore, operation may result in excellent long-term quality of life.

A misplaced caval filter: its removal from the heart without cardiopulmonary bypass.

Placement of metallic filters into the inferior vena cava for the prevention of pulmonary embolism has become a popular procedure that has reportedly little morbidity. The present case describes the misplacement of a Kim-Ray Greenfield filter into the right atrium and the subsequent successful removal of the device without the use of cardiopulmonary bypass.

FDG imaging of a pulmonary artery sarcoma.

Fluorine-18-2-fluro-2-deoxy-D-glucose-positron emission tomographic tumor imaging was employed to aid in the diagnosis of a patient with a right hilar mass. Based on preoperative imaging and intraoperative findings, a right pneumonectomy was performed for what proved to be a pulmonary artery sarcoma.

Autotransfusion following cardiac operations: a randomized, prospective study.

To evaluate the safety and effectiveness of the collection and retransfusion of postoperatively shed mediastinal blood as part of a multifaceted approach to blood conservation following cardiac operation, 113 patients were randomized into either an autotransfusion group (54 patients) or a control group (59 patients). Intraoperative and postoperative hemodilution was practiced in all patients. The clinical safety of this technique was confirmed by the lack of septic, hematological, pulmonary, renal, or hepatic complications. However, in this setting where blood conservation is already aggressively practiced, the ability of the technique to further reduce the use of banked blood following cardiac surgical procedures was not demonstrated.

Cardiopulmonary bypass and pulmonary thromboxane generation.

Sporadic cases of inexplicable noncardiogenic pulmonary edema occur after operations requiring total cardiopulmonary bypass (CPB). Prostaglandins, such as thromboxane (Tx) A2, have been implicated in this form of pulmonary pathology in many clinical and experimental settings. Because Tx generation has been demonstrated in association with ischemia of solid organs, we postulated that total CPB, which decreases pulmonary tissue perfusion and oxygenation, would stimulate local Tx synthesis. Total CPB was examined in 7 sheep. The level of TxB2 (a stable metabolite of the active, unstable A2) was measured in the left and right atria before, during, and after 105 minutes of total CPB. Significant increases in TxB2 concentrations occurred in the left atrium compared with the right (p < 0.05) during CPB. Immediately after reperfusion, both the left atrial and right atrial TxB2 concentrations increased significantly over the baseline values (p < 0.05), but this increase and the atrial gradient were rapidly abolished with continued pulmonary perfusion. To determine the effect of extracorporeal circulation without significant (< 30%) alteration in pulmonary perfusion, we evaluated the effect of partial CPB in 5 sheep. Increased TxB2 concentrations were noted at 15 and 30 minutes after the onset of partial CPB (left atrium increased significantly over baseline; p < 0.05), but this elevation spontaneously diminished to insignificance after 15 and 30 additional minutes of extracorporeal circulation. These data establish that total CPB stimulates Tx generation in the lung, and although the effect of partial CPB is transient, that of total CPB is progressive and abolished by reperfusion.(ABSTRACT TRUNCATED AT 250 WORDS)

Aortic valve operation after percutaneous aortic balloon valvuloplasty.

From January 1986 to May 1988, 179 patients underwent percutaneous aortic balloon valvuloplasty at our institution. Forty-five (25%) patients subsequently required operation at this institution or other institutions. The indication for percutaneous aortic balloon valvuloplasty was patient preference in 15 and an estimation of excessive operative mortality in 30. Three patients required emergency operation immediately after valvuloplasty, and the other 42 had an elective operation a mean of 7.8 months afterward. All but 3 of these patients had major progression of symptoms, and all had valvular restenosis. In spite of the high-risk status of these patients, there were only four hospital deaths among the 45 patients. Three additional patients have died a mean of 11.4 months postoperatively. The condition of all survivors remains clinically improved after the valve operations. Percutaneous aortic balloon valvuloplasty must be recognized as a palliative procedure, and should be reserved for patients who are truly not candidates for operation or situations in which a brief period of reduction in gradient might improve a patient's condition before operation.

Ultrasonic debridement of calcified pericardium in constrictive pericarditis.

Debridement of heavily calcified and adherent pericardium with an ultrasonic surgical aspiration device is described. The device proved to be a useful adjunct to the complete debridement of densely adherent pericardium.

Moderate hypothermia reduces cardiopulmonary bypass-induced impairment of cerebrovascular responses to platelet products.

BACKGROUND: The purpose of this study was to determine whether cerebral cortical microvascular responses to platelet-derived vasoactive substances are altered after normothermic cardiopulmonary bypass (CPB), and whether these alterations are modified by moderate hypothermia. METHODS: Pigs were placed on normothermic CPB (37 degrees C) for 2 hours and then perfused off CPB with normothermic blood for either 15 minutes (n = 8) or 60 minutes (n = 6). Another group was placed on moderately hypothermic CPB (25 degrees C) for 2 hours and then perfused off CPB at 37 degrees C for 15 minutes (n = 6). Alphastat pH management was used. In vitro responses of isolated cortical cerebral arterioles (90 to 170 microns internal diameter) to platelet-derived vasoactive substances were examined in a pressurized no-flow state with videomicroscopy. Microvessels from noninstrumented pigs (n = 14) were used as controls for in vitro studies. RESULTS: Cerebrovascular resistance and internal carotid artery blood flow were similar 15 minutes after CPB in both normothermic and hypothermic groups. However, relaxations of microvessels to adenosine 5' diphosphate or serotonin were reduced in vessels from both groups. One hour of after CPB cerebral perfusion did not change this pattern of altered vascular reactivity. Hypothermia caused a partial but significant reduction in impairment of responses to adenosine 5' diphosphate and serotonin. Microvascular relaxation to the endothelium-independent agent sodium nitroprusside and contraction to a thromboxane A2 analog were similar in all experimental groups, suggesting normal vascular smooth muscle responsiveness. CONCLUSIONS: This study demonstrates that normothermic extracorporeal circulation reduces endothelium-dependent relaxation responses to products of platelet activation in the cerebral microcirculation. Moderate hypothermia attenuates the CPB-induced impairment of endothelium-dependent relaxation, but has no effect on baseline cerebral blood flow after rewarming.

Aortic valve replacement and coronary bypass in patients with severe stenosis of the left main coronary artery.

Adequate myocardial protection is difficult to achieve during operations for combined aortic valve disease and severe stenosis of the left main coronary artery. A double cross-clamp technique, which facilitates the delivery of cardioplegic solution to the myocardium, is described here. We reviewed the experiences of 11 patients, 6 of whom underwent operation using the new technique.

Functional benefits following coronary artery bypass graft surgery.

While some studies of patients who undergo cardiac surgery have included such outcome measures as amounts of symptom reduction and rates of resumption of employment, little attention has been focused on the extent to which these patients have experienced the simple, yet very important, broad range of functional benefits that might be anticipated by clinicians to result from operation. The present report seeks to document the extent of improvement that does exist in terms of physical, sexual, and social-role functioning. In a cohort of 340 patients (age, 32 to 69 years) studied before and six months after coronary artery bypass operation, improvements were noted in each of three dimensions of functional benefit: physical functioning (fewer total activity restrictions or incapacitated days per month), sexual functioning (through increased energy and desire and decreased pain and worry), and role functions (ability to work, social participation, and pursuit of hobbies). Further improvements might be anticipated with additional months of recovery.

Lidocaine prophylaxis in coronary revascularization patients: a randomized, prospective trial.

Life-threatening ventricular ectopy can occur after cardiac operations. The actual incidence of ventricular ectopy and the ability to prevent it by the routine prophylactic use of lidocaine hydrochloride have not been established. We performed a double-blind, randomized, prospective trial involving 109 patients undergoing elective coronary artery revascularization. Patients received either lidocaine (n = 54) or a placebo (n = 55) after separation from bypass. A Holter monitor was affixed to each patient for subsequent review, and bedside intensive-care monitors with alarms were used for "real-time" surveillance. The code was broken when potentially malignant ventricular ectopy or side effects attributable to the study drug were noted. Three lidocaine patients and 2 placebo patients were dropped from the study because of hemodynamic instability or bleeding. Of the remaining 104 patients, the code was broken in 12 (24%) of the 51 in the lidocaine group (9 for ectopy and 3 for mental status changes) and 10 (19%) of the 53 in the placebo group (all for ectopy) (p = not significant). Twenty-four-hour Holter monitor evaluation demonstrated occasional ventricular ectopy in all patients and nonsustained ventricular tachycardia in 28% in the lidocaine group and 48% in the placebo group (p = not significant). The mean number of runs of ventricular tachycardia per patient was 0.53 in the lidocaine group and 1.6 in the placebo group (p = 0.035). There were no significant differences in terms of other ventricular ectopy, morbidity, or mortality. No ventricular fibrillation occurred in either group.(ABSTRACT TRUNCATED AT 250 WORDS)

Impact of acute reduction in chronically elevated left atrial pressure on sodium and water excretion.

To test the hypothesis that a reduction in chronically elevated left atrial pressure would decrease sodium and water excretion in humans, we studied 61 carefully selected patients who underwent cardiac surgery for valvular or coronary artery disease or both. The immediate postoperative decrease in left atrial pressure (from 16.7 +/- 1.0 to 9.4 +/- 0.4 mm Hg; p less than 0.001) was inversely correlated with postoperative urine output (r = -0.69; p less than 0.001) and sodium excretion (r = -0.51; p less than 0.005). There was no significant relationship between postoperative urine output or sodium excretion and other hemodynamic or nonhemodynamic variables. A significant postoperative decrease in plasma atrial natriuretic factor (from 150 +/- 22 to 65 +/- 14 pg/ml; p less than 0.01) and increase in plasma renin activity (from 2.5 +/- 0.6 to 8.7 +/- 3.2; p less than 0.05) occurred in patients with a 7 mm Hg or greater postoperative decrease in left atrial pressure. Thus, an acute reduction in left atrial pressure results in significant reductions in urine output and sodium excretion, the magnitude of which are related to the degree of reduction in left atrial pressure.

Preparation of valved conduits by plasma immersion and autoclaving.

A method is described for preparing the graft portion of a manufactured valved conduit by plasma immersion and autoclaving while protecting the attached mechanical valve from coagulum and debris.

Predictors of CABG within one year of successful PTCA: a retrospective, case-control study.

BACKGROUND: We previously have established characteristics predictive of the need for coronary artery bypass grafting (CABG) over many years after successful percutaneous transluminal coronary angioplasty (PTCA). In this study, we examined the factors associated with the need for CABG within 1 year of successful PTCA, and the recent impact of newer, catheter-based technologies. METHODS: From January 1982 through December 1995, 234 patients underwent CABG within 1 year of a successful "index" PTCA at our hospital. Emergency operations within 12 hours of index PTCA were excluded. These cases were matched with 234 controls who underwent a successful index PTCA but did not require a subsequent CABG during the next year. Cases were matched by the date of their index PTCA, and 1-year follow-up was complete for all patients. RESULTS: Before index PTCA there were no differences between the groups in terms of age, sex, diabetes, prior myocardial infarction, ejection fraction, duration of anginal symptoms, hypertension, hyperlipidemia, family history, or obesity (all nonsignificant). At index PTCA the cases had a greater mean number of lesions measuring 70% or greater compared with the controls (2.8 versus 1.8, respectively; p < 0.0001). The cases were more likely to have critical (70% or greater) proximal left anterior descending artery, proximal first obtuse marginal artery, and right posterior descending artery stenoses. The use of stents or atherectomy devices was not significantly more common among the controls (21% of controls versus 17.1% of cases; p = 0.35). Complete revascularization was achieved in significantly fewer of the cases than the controls (91 versus 156, respectively; p < 0.0001). The cases underwent CABG at a mean of 3 months (86% within 6 months) after PTCA. Among those who had a diagnostic catheterization, 52% of the patients had both restenosis of a dilated lesion and progression of other disease. Only 5 of 75 patients who had restenosis of a dilated lesion had a stent or an atherectomy device used at index PTCA. Of note, 13% (30 of 234) required an emergency operation, with an overall operative mortality rate of 3% (7 of 234). CONCLUSIONS: Although the likelihood of local restenosis is decreased by newer interventional techniques, the need for CABG within 1 year after successful PTCA is not diminished. The number of critical lesions and their location are the best predictors of the need for early CABG. If early post-PTCA CABG is to be avoided, patients who cannot be completely revascularized by PTCA should be revascularized by CABG.