Expression of the apical conjugate export pump, Mrp2, in the polarized hepatoma cell line, WIF-B

We have investigated the effect of N-acetylcysteine on hemodynamic variables, oxygen delivery (DO2), oxygen consumption (VO2), and oxygen extraction in patients with fulminant hepatic failure using independent methods of determining DO2 and VO2, thereby eliminating the effect of mathematical coupling, which may have biased previous studies. In 11 patients with severe fulminant hepatic failure, we documented the hemodynamic effects of N-acetylcysteine during the first 5 hours of a standard infusion regime and simultaneously measured VO2 using a method based on respiratory gas analysis. We related physiological changes to plasma N-acetylcysteine concentrations, and compared this group with 7 patients who received placebo infusions. A variable hemodynamic response to N-acetylcysteine was observed that did not differ significantly in comparison with the placebo group, and did not correlate with plasma drug concentrations. The most significant relationship observed between DO2 and VO2 in any patient predicted a 13-mL x min(-1) x m(-2) increase in VO2 when DO2 increased by 100 mL x min(-1) x m(-2); in 8 patients, VO2 was independent of DO2 over the range observed. In the group that received N-acetylcysteine, a small (mean 6 [SD 6] mL x min(-1) x m[-2]) increase in VO2 occurred in comparison with baseline after 1 hour of infusion (P < .01), but changes were not significantly different from the placebo group and were not sustained. N-Acetylcysteine infusion did not increase oxygen extraction or result in an improvement in whole-blood lactate levels or base excess during the study period. We conclude that N-acetylcysteine infusion does not result in clinically relevant improvements in global VO2, or in clinical markers of tissue hypoxia in patients with severe fulminant hepatic failure.     

Effects of concomitant usage of milrinone and catecholamine for weaning from cardiopulmonary bypass

To estimate the effectiveness of concomitant usage of milrinone and catecholamine for weaning from cardiopulmonary bypass (CPB), a clinical study was made, in elective coronary artery bypass grafting (CABG) cases. 24 consecutive patients underwent elective CABG in our institute. In all cases, moderate hypothermia and cardioplegic(St. Thomas solution) cardiac arrest were performed. In 12 cases, continuous intravenous 0.25 microgram/kg/min of milrinone, 3 micrograms/kg/min of dobutamine (DOB) and dopamine (DOA) as the initial doses, were used concomitantly as inotropic agents (Group-I). The same initial doses of catecholamine (DOB and DOA) as the Group-I were administered in another 12 patients (Group-II). When the pump flow of CPB decreased to a half, these drugs were administered in both groups. Hemodynamic data were measured before CPB, just after operation, 3, 6, 12, 24, 48, and 72 hours after operation. There were no significant differences in aortic and pulmonary artery pressure between both groups. However, cardiac index (CI) of the Group-I demonstrated significantly (p < 0.01) higher values than that of Group-II until 24 hours after surgery. Systemic vascular resistance index (SVRI) of the Group-I demonstrated significantly (p < 0.01) lower value than that of Group-II from 3 to 12 hours after operation. There were no significant differences in oxygen delivery (DO2) and oxygen consumption (VO2) between both groups. These results suggested that concomitant usage of milrinone and low dose catecholamine increased CI and decreased SVRI, and made weaning from CPB very easy, demonstrating excellent hemodynamics. This high potential phosphodiesterase inhibitor may be suitable for not only weaning from CPB but also post-cardiotomy cardiogenic shock.     

Decisions about enteral tube feeding among the elderly

OBJECTIVE: To characterize the acute actions and physiologic dose profile of epinephrine, as a single inotrope, in patients with septic shock. DESIGN: Prospective clinical study. The relationship between epinephrine dose and cardiovascular variables was analyzed using repeated-measures analysis of variance. SETTING: ICU in a university teaching hospital. PATIENTS: Eighteen patients with septic shock, mean age 64 +/- 8 (SD) yrs, and with a mean admission Acute Physiology and Chronic Health Evaluation (APACHE II) score of 23 (range 14 to 35). INTERVENTIONS: Initial volume loading and the measurement of a baseline hemodynamic profile were followed by the administration of an epinephrine infusion at 3 microgram/min with subsequent increments of 3 micrograms/min and the determination of a hemodynamic profile after each dose increment. Therapy was titrated to clinical goals of perfusion and restoration of premorbid systolic arterial BP. MEASUREMENTS AND MAIN RESULTS: After volume loading, mean hemodynamic indices were as follows: mean arterial pressure (MAP) 62 +/- 7 mm Hg; cardiac index 3.8 +/- 1.1 L/min/m2; left ventricular stroke work index 25 +/- 11 g.m/m2; oxygen delivery (Do2) index 460 +/- 168 mL/min/m2; and oxygen consumption (VO2) index 165 +/- 64 mL/min/m2. In the dose range of 3 to 18 microgram/min, epinephrine produced linear increases in average heart rate, MAP, cardiac index, left ventricular stroke work index, stroke volume index, VO2, and DO2. No effect was noted on pulmonary artery occlusion pressure (PAOP), mean pulmonary arterial pressure, or systemic vascular resistance index. CONCLUSIONS: Epinephrine increases DO2 in septic shock by increasing cardiac index without an effect on systemic vascular resistance index or PAOP.     

Genetic analysis of adult-onset cataract in a city-based ophthalmic hospital

When oxygen delivery (DO2) critically decreases, oxygen consumption (VO2) becomes supply dependent. We examined whether end-tidal PCO2 (PetCO2) would identify supply dependency during shock. Five dogs (Group I) underwent progressive hemorrhage to decrease DO2 until they could no longer maintain a stable blood pressure. Five additional animals (Group II) were bled until VO2 decreased to 70% of baseline, followed by resuscitation. The PetCO2 versus time inflection point was compared with the DO2 at onset of supply dependency (DO2crit). DO2crit for Groups I and II were 6.9 +/- .4 and 8.1 +/- 1.3, respectively (p = NS), and not statistically different from the DO2 values at which PetCO2 decreased (6.6 +/- .7 and 6.3 +/- .7 mL/kg per min, respectively). AT constant minute volume, PetCO2 effectively indicated the onset of supply dependency and rapidly increased during resuscitation, paralleling the changes in VO2 in this model of hemorrhagic shock.     

Elevated arterial base deficit in trauma patients: a marker of impaired oxygen utilization

BACKGROUND: In trauma patients, the admission value of arterial base deficit stratifies injury severity, predicts complications, and is correlated with arterial lactate concentration. In theory, elevated base deficit and lactate concentrations after shock are related to oxygen transport imbalance at the cellular level. The purpose of this study was to test the hypothesis that an elevated base deficit in trauma patients is indicative of impaired systemic oxygen utilization and portends poor outcomes. METHODS: This study was a retrospective analysis of a prospectively collected database. The study population included all patients admitted to the trauma intensive care unit at a Level 1 trauma center during a 12-month period who were monitored with a pulmonary artery catheter and serial measurements of lactate and base deficit, and who achieved a normal arterial lactate concentration (< 2.2 mmol/L) with resuscitation. The patients were divided into those who maintained a persistently high base deficit (> or = 4 mmol/L) and those who achieved a low base deficit (< 4 mmol/L) during resuscitation. RESULTS: One-hundred patients (mortality 20%) were monitored with a pulmonary artery catheter and achieved a normal arterial lactate concentration. The mean age+/-SD (SEM) of the group was 37+/-17 years and the Injury Severity Score was 25+/-11. Subgroup analysis revealed that patients with a persistently high base deficit (n=26) had higher rates of multiple organ failure (35% versus 5%, p < 0.001) and death (50% versus 9%, p < 0.00001) compared with patients who achieved a low base deficit. Patients with a persistently high base deficit also had lower oxygen consumption (126+/-40 mL/m2 versus 156+/-30 mL/m2, p=0.01 at 48 hours) and a lower oxygen utilization coefficient (0.20+/-0.05 versus 0.24+/-0.03, p=0.01 at 48 hours) compared with patients with a low base deficit. At 48 hours, both oxygen consumption (r=-0.44, [r, correlation coefficient] p=0.002) and oxygen utilization (r=-0.46, p=0.001) had a significant negative correlation with base deficit. CONCLUSIONS: In trauma patients, a persistently high arterial base deficit is associated with altered oxygen utilization and an increased risk of multiple organ failure and mortality. Serial monitoring of base deficit may be useful in assessing the adequacy of oxygen transport and resuscitation.     

Hepatic blood flow and splanchnic oxygen consumption in patients with liver failure. Effect of high-volume plasmapheresis

Liver failure represents a major therapeutic challenge, and yet basic pathophysiological questions about hepatic perfusion and oxygenation in this condition have been poorly investigated. In this study, hepatic blood flow (HBF) and splanchnic oxygen delivery (DO2, sp) and oxygen consumption (VO2,sp) were assessed in patients with liver failure defined as hepatic encephalopathy grade II or more. Measurements were repeated after high-volume plasmapheresis (HVP) with exchange of 8 to 10 L of plasma. HBF was estimated by use of constant infusion of D-sorbitol and calculated according to Fick's principle from peripheral artery and hepatic vein concentrations. In 14 patients with acute liver failure (ALF), HBF (1.78 +/- 0.78 L/min) and VO2,sp (3.9 +/- 0.9 mmol/min) were higher than in 11 patients without liver disease (1.07 +/- 0.19 L/min, P <.01) and (2.3 +/- 0.7 mmol/min, P <.001). In 9 patients with acute on chronic liver disease (AOCLD), HBF (1.96 +/- 1.19 L/min) and VO2,sp (3.9 +/- 2.3 mmol/min) were higher than in 18 patients with stable cirrhosis (1.00 +/- 0.36 L/min, P <.005; and 2.0 +/- 0.6 mmol/min, P <.005). During HVP, HBF increased from 1.67 +/- 0.72 to 2.07 +/- 1.11 L/min (n=11) in ALF, and from 1.89 +/- 1.32 to 2.34 +/- 1.54 L/min (n=7) in AOCLD, P <.05 in both cases. In patients with ALF, cardiac output (thermodilution) was unchanged (6.7 +/- 2.5 vs. 6.6 +/- 2.2 L/min, NS) during HVP. Blood flow was redirected to the liver as the systemic vascular resistance index increased (1,587 +/- 650 vs. 2, 020 +/- 806 Dyne. s. cm-5. m2, P <.01) whereas splanchnic vascular resistance was unchanged. In AOCLD, neither systemic nor splanchnic vascular resistance was affected by HVP, but as cardiac output increased from 9.1 +/- 2.8 to 10.1 +/- 2.9 L/min (P <.01) more blood was directed to the splanchnic region. In all liver failure patients treated with HVP (n=18), DO2,sp increased by 15% (P <.05) whereas VO2,sp was unchanged. Endothelin-1 (ET-1) and ET-3 were determined before and after HVP. Changes of ET-1 were positively correlated with changes in HBF (P <.005) and VO2,sp (P <.05), indicating a role for ET-1 in splanchnic circulation and oxygenation. ET-3 was negatively correlated with systemic vascular resistance index before HVP (P <.05) but changes during HVP did not correlate. Our data suggest that liver failure is associated with increased HBF and VO2, sp. HVP further increased HBF and DO2,sp but VO2,sp was unchanged, indicating that splanchnic hypoxia was not present.     

Severe depression of gut absorptive capacity in patients following trauma or sepsis

Although clinical studies suggest enteral, as opposed to parenteral, feeding lowers morbidity and mortality rates following severe trauma and after sepsis, it is unknown whether gut absorptive capacity (GAC) is indeed maintained under such conditions. To study this, GAC was determined in patients with blunt trauma (n = 8) and with sepsis (n = 11) by the 1-hour D-xylose absorption test. Excluded were patients with ileus, nasogastric output of more than 600 mL/24 hours, or residual gastric content of more than 25 mL after the D-xylose test. Trauma patients (ISS 8-14) and patients with intra-abdominal sepsis had an initial D-xylose test within 24 to 48 hours of admission, at 72 to 96 hours, and then weekly until D-xylose absorption had returned to normal. D-xylose (25 g in 200 mL water) was given via nasogastric tube to patients and orally to healthy volunteers (controls: n = 8). Results show that GAC was depressed at 24 to 96 hours in both groups but returned to normal by 1 to 3 weeks after trauma or resolution of sepsis. Thus (1) gut absorptive capacity was severely depressed early after trauma and after the onset of sepsis; and (2) the 1-hour D-xylose absorption test provided a simple, quantitative assessment of GAC in critically ill patients. Hence, therapeutic agents that restore gut absorptive capacity may be useful for further reducing morbidity and mortality rates following trauma or the onset of sepsis.     

Clinical and toxicological data in fenthion and omethoate acute poisoning

This study paper reports on two cases of poisoning with the organophosphorus insecticides, fenthion and omethoate. The two victims were admitted in the Intensive Care Unit (ICU) a few hours after ingestion of the two insecticides. They received appropriate treatment for organophosphorous poisoning (gastric lavage, activated charcoal, atropine and pralidoxime) and supportive care. Both patients survived. Organophosphate blood levels were determined on admission (fenthion 2.9 micrograms/ml, omethoate 1.6 micrograms/ml) and during the hospitalisation and proved to be considerably high. Slow elimination rate of the poison already distributed in the body was indicated for both pesticides. The patient with omethoate poisoning remained clinically well (Glasgow Coma Scale: 15) and was discharged three days later. The patient with fenthion poisoning, who had also ingested 30 mg of bromazepam and 720 mg of oxetoron, developed cholinergic crisis six hours after admission and was intubated for 24 days, with concomitant complications.     

Oxygen delivery in critical illness

Oxygen consumption is physiologically dependent on DO2 below the critical DO2. Thus, patients in overt shock have physiologic dependence of VO2 on DO2. The first priority of prevention and reversal of tissue hypoxia is to balance oxygen demand and oxygen supply. Pathologic dependence of VO2 on DO2 has not yet been demonstrated convincingly in critically ill patients. Furthermore, in our opinion, contradicting results of RCTs of supernormal DO2 versus normal DO2 do not support routine maintenance of supernormal levels of DO2. Finally, we suggest that intensivists continue to assess DO2 and VO2 carefully. Global assessment of VO2 and DO2 appears inadequate to detect occult tissue hypoxia in most critically ill patients. However, research focused on regional assessment such as gastric tonometer measurement of gastric mucosal PCO2 and pH provides opportunity for safe, convenient detection of occult tissue hypoxia in critically ill patients.     

Oxygen transport and oxygen metabolism in shock and critical illness. Invasive and noninvasive monitoring of circulatory dysfunction and shock

The common underlying physiologic problem in shock is low flow from hypovolemia or maldistributed microcirculatory flow from uneven vasoconstriction, leading to inadequate tissue perfusion (hypoxia), often in the face of increased metabolic demands. Noninvasive monitoring which was found to provide similar information to that of invasive monitoring, was used in the earliest period of time shortly after admission to the emergency department to provide objective physiologic criteria as therapeutic goals for each of the three major circulatory components: cardiac, pulmonary, and tissue perfusion functions. A clinical algorithm or branch-chain decision tree for high-risk surgical patients was developed from decision rules based on survivor and nonsurvivor patterns, outcome predictors, prospective controlled clinical trials of the oxygen delivery/oxygen consumption (DO2/VO2) concept, and the DO2/VO2 responses of a wide variety of therapeutic agents.     

Impact on the immune system of undetectable plasma HIV-1 RNA for more than 2 years

The role of ICU support in BMT patients is controversial. In an era of constrained resources, the use of prognostic factors predicting outcome may be helpful in identifying patients who are most likely (or unlikely) to benefit from this intervention. We attempted to define the survival of patients admitted to ICU following autologous or allogeneic BMT and to identify those factors important in determining patient outcome. A retrospective study of all adult BMT recipients admitted to intensive care over a 6 year study period was performed to determine overall and prognostic indicators of poor outcome. Pre-treatment, pre-ICU admission and ICU admission data were analyzed to identify factors predicting long-term survival. 116 patients were admitted to ICU on 135 separate occasions with the primary reasons for admission being respiratory failure (66%), sepsis associated with hypotension (10%), and cardiorespiratory failure (8%). No pre-ICU characteristics were predictive of survival. Univariate analysis identified the number of support measures required, the need for ventilation or hemodynamic support, the APACHE II score, the year of ICU admission and the serum bilirubin as significant predictors of post-discharge survival. On multivariate analysis the year of ICU admission, the need for hemodynamic support and the serum bilirubin remained significant. The APACHE II score significantly underestimated survival in the 46% of patients with scores less than 35, and could only be used to predict 100% mortality when it exceeded 45. Twenty-three percent of all BMT patients admitted to the ICU and 17% of ventilated patients survived to hospital discharge. Of the 27 patients surviving to leave hospital, 16 remain alive with a median follow-up of 4.2 years and a mean Karnofsky performance status of 90. Although mortality in BMT recipients admitted to ICU is high our results indicate that intensive care support can be lifesaving and that the outcome in patients requiring ventilation and ICU support may not be as poor as has been previously reported. No single variable was identified which could be used to predict futility but patients requiring both hemodynamic support and mechanical ventilation, and those with an APACHE II score greater than 45 have a very poor prognosis and are unlikely to benefit from lengthy ICU support.     

Short-term effects of methylene blue on hemodynamics and gas exchange in humans with septic shock

OBJECTIVE: The aim of this study was to investigate the acute effects of methylene blue (MB), an inhibitor of the L-arginine nitric oxide pathway, in patients with septic shock. DESIGN: A prospective, open, single-dose study. SETTING: The medical ICU of a university hospital. PATIENTS: Six patients with severe septic shock. INTERVENTIONS: Complete hemodynamic values were recorded before and 20 min after the infusion of intravenous MB (3 mg kg(-1)). Arterial pressure was then monitored during the next 24 h or until death. MEASUREMENTS AND RESULTS: Methylene blue increased the mean arterial pressure from 69.7 +/- 4.5 to 83.7 +/- 5.1 mmHg (p = 0.028) and the mean pulmonary artery pressure, from 34.3 +/- 7.2 to 38.7 +/- 8.0 mmHg (p = 0.023). Systemic vascular resistance index was increased from 703.1 +/- 120.6 to 903.7 +/- 152.2 dyne.s.cm(-5).m(-2) (p = 0.028) and pulmonary vascular resistance index, from 254.6 +/- 96.9 to 342.2 +/- 118.9 dyne.s.cm(-5) .m(-2) (p = 0.027). The PaO2/FIO2 decreased from 229.2 +/- 54.4 to 162.2 +/- 44.1 mmHg (p = 0.028), without significant modification of intrapulmonary shunting. Heart rate, cardiac index, right atrial pressure, DO2, VO2, oxygen extraction and arterial lactate were essentially unchanged. Sequential measurements of arterial pressure demonstrated a return to baseline level in 2-3 h. All but one patients died, three in shock and two in multiple organ failure. CONCLUSIONS: MB induces systemic and pulmonary vasoconstriction in patients with septic shock, without significant decrease in cardiac index. The worsening of arterial oxygenation following MB injection may limit its use in patients with the adult respiratory distress syndrome. Larger studies are required to determine whether MB improves the outcome of patients with septic shock.     

A randomized comparison of exercise training in patients with normal vs reduced ventricular function

BACKGROUND: Exercise training is recommended after myocardial infarction (MI) or bypass surgery in order to improve exercise tolerance. In some patients, the decrement in exercise capacity secondary to deconditioning and the left ventricular stunning associated with MI or coronary artery bypass graft (CABG) spontaneously improves after the event. However, the impact of the status of the left ventricle on these improvements is unknown. METHODS: Sixty-seven patients 1 month after MI or CABG were randomized to a training (n=34; age, 59+/-7 years) or a control group (n=33; age, 55+/-6 years). Forty-two patients had an ejection fraction >50% (22 in the training group and 20 in the control group), and 25 patients had an ejection fraction <40% (12 in the exercise group and 13 in the control group). After stabilization for approximately 1 month after the event, patients in the exercise group underwent 8 weeks of twice daily exercise at a residential rehabilitation center, while control patients received usual care. Initially and after 8 weeks, patients in both groups underwent maximal exercise testing with gas exchange and lactate analysis. RESULTS: Exercise training increased peak oxygen consumption (VO2) only in the reduced ejection fraction group (19.4+/-3.0 to 23.9+/-4.8 mL/kg/min; p<0.05); the exercise group with normal ventricular function did not change significantly. Changes in VO2 at the lactate threshold paralleled those of peak VO2 for both groups. Conversely, control patients with normal ventricular function increased peak VO2 spontaneously (20.8+/-3.9 to 24.8+/-3.5 mL/kg/min; p<0.01), whereas control patients with reduced ventricular function did not improve peak VO2. CONCLUSION: These data suggest that patients with depressed left ventricular function strongly benefit from rehabilitation, whereas most patients with preserved left ventricular function following MI or CABG tend to improve spontaneously 1 to 3 months after the event.     

Differences in mortality between elderly and younger adult trauma patients: geriatric status increases risk of delayed death

BACKGROUND: Elderly patients suffer higher mortality rates after trauma than younger patients. This increased mortality is attributable to age, preexisting disease, and complications as well as injury severity. METHODS: Records from 5,139 adult patients from a Level I trauma center were retrospectively reviewed. Injury Severity Score (ISS), Revised Trauma Score (RTS), early mortality (<24 hours), and late mortality (>24 hours) were determined for elderly (> or =65 years) and younger (16-64 years) patients. Preexisting diseases and complications were identified by International Classification of Diseases, Ninth Revision, Clinical Modification diagnosis coding. RESULTS: Mortality in elderly patients was twice that in younger patients despite equivalent injury severity (p < 0.001), and elderly patients were more likely to suffer later death than younger patients (p < 0.005). The prevalence of preexisting disease was greater in the elderly, as was the incidence of complications. Using logistic regression, ISS, RTS, preexisting cardiovascular or liver disease, the development of cardiac, renal, or infectious complications, and geriatric status were all independently predictive of late mortality (p < 0.05). CONCLUSION: Elderly trauma patients more frequently suffer late mortality than younger patients because of the combination of injury and increased preexisting disease and complications after injury. Aggressive treatment of the elderly trauma patient is warranted; however, in the face of significant preexisting disease or complications, survival is less likely. Predictive models of survival can be developed, taking into account preexisting disease and complications as well as admission parameters such as age, ISS, and RTS, and specific risk of mortality quantitated.     

Effects of dobutamine, norepinephrine and epinephrine on intramucosal pH and hemodynamics of dogs during endotoxic shock

This study assessed the effects of dobutamine (DOB), epinephrine (EPI) and norepinephrine (NE) on gastric tissue oxygenation indicated by gastric intramucosal pH (pHi) and hemodynamics in dogs subjected to endotoxic shock. Twenty-four dogs were assigned to four groups of 6 dogs each: endotoxin without catecholamine and endotoxin with DOB, or EPI or NE. Endotoxic shock was induced by intravenous injection of 3 mg/kg of E. coli over 1 min, with an additional 3 mg/kg over the next 2 hrs. Dogs were resuscitated with normal saline to maintain pulmonary capillary wedge pressure (PCWP) near baseline levels. Catecholamines were infused at 0.1, 0.4 and 1.6 micrograms/kg/min (EPI and NE) and 2.5, 5.0 and 10.0 micrograms/kg/min (DOB) for 30 min at each rate. After 2 hrs of endotoxemia, mean arterial pressure (MAP) and cardiac index (CI) and oxygenation delivery index (DO2I) for all dogs decreased by 46.5%, 43.9% and 15.1% respectively, while pHi decreased from 7.47 to 7.10. Endotoxemia increased blood lactate by 142%. Following fluid resuscitation, EPI (1.6 micrograms/kg/min) further increased lactate by 178% (1.22 to 3.4 mmol/L). No correlation was found between tonometry pHi and lactate (R2 = 0.003), pHi and pHa (R2 = 0.231), pHi and DO2I (R2 = 0.056) nor between intramucosal PCO2 and PaCO2 (R2 = 0.005). pHi did not reflect the improvements in cardiovascular hemodynamics observed following administration of catecholamines. NE improved MAP, CI and DO2I whereas DOB produced similar effects as NE but further reduced SVR. EPI produced similar effects as NE. DOB, NE and EPI further decreased pHi. EPI significantly (P < 0.05) increased blood lactate levels more than DOB and NE.     

Diagnostic problems of circumscribed myositis ossificans: presentation of an atypical case

BACKGROUND: Thrombosis of mechanical prosthetic heart valves (TMPHV) is one of the major complications that accounts for the highest morbidity and mortality related to Bileaflet Mechanical Prosthetic Heart Valves (BMPHV). MATERIALS AND METHODS: During the last six years we had ten cases of bileaflet mechanical valve thrombosis. All patients had undergone emergency surgical interventions except one who developed systemic embolization and massive brain insult immediately after admission for surgery and died two months later. We divided the patients in two groups, first group includes five patients who came in acute pulmonary edema and emergency operation was done either to replace the thrombosed BMPHV (in two) or successful thrombectomy was achieved (in three) and all of them have survived. The second group (four patients) presented with cardiogenic shock and required emergency femoro-femoral bypass. Two patients survived after thrombectomy and the other two could not come off bypass after changing the TMPHV and in spite of Intra-aortic balloon pump, they died 24 and 48 hours after the procedure. All patients received intravenous heparin on admission. Preoperative i.v. Streptokinase was given in two cases, of which one required thrombectomy and the other had valve replacement and died 24 hours later. RESULTS: Early diagnosis and operation still had the best results in TMPHV though thrombolytic therapy was successful in few reported early presented cases. All patients who had thrombectomy of the TMPHV have survived without any morbidity. Follow up of survived patients ranged between two months and six years with a mean of 24.1 months. It is worth attempting thrombectomy of the thrombosed BMPHV rather than re-replacement which carries higher morbidity and mortality, because of the longer ischemic arrest during operation which further depletes the energy of the myocardium. CONCLUSIONS: Though this is a small number of patients to make a definite conclusion, thrombectomy was more feasible in CarboMedics Prosthetic Heart Valves, since its in situ rotation that allows reorientation of its leaflets and declotting of valve hinge to be performed.     

Differentiation of benign and malignant cervical lymph nodes: value of B-mode and color Doppler sonography

AIM: Acute mesenteric ischemia is difficult to diagnose and is combined with a high mortality. In a retrospective analysis it was investigated how to improve the poor prognosis of the disease. PATIENTS AND METHODS: Between January 1988 through December 1994 a total of 46 patients were operated on for acute mesenteric ischemia. Mesenteric artery occlusion was present in three quarters of the cases (n = 35). These were analysed according to symptoms, diagnosis, mechanism of occlusion, operative procedure and prognosis. Distribution of gender was almost balanced (19 women, 16 men) with a median age of 70.5 years. RESULTS: Embolic arterial occlusion was predominant (n = 22). Most frequently, the superior mesenteric artery was exclusively concerned (n = 22). Serum levels of lactate and leucocytes were preoperatively elevated in over 90% (median values: lactate 53 U/l, leucocytes 15050/ml). In 16 patients diagnosis was made on the ground of clinical parameters and/or angiography, but 19 patients were not diagnosed until operation. 19 patients were operated within 6 hours, 12 patients within 24 hours after admission (> 24 hours: n = 4). Vascular reconstructive procedures only, such as thrombectomy and/or aortomesenteric bypass were performed in 9 cases, in a further 7 cases combined with bowel resection. Bowel resection alone was done in 7 patients, 12 patients had only diagnostic laparotomy. 13 patients survived, 10 of them had been treated with vascular reconstruction. CONCLUSION: Acute mesenteric ischemia ought to be suspected in every patient with uncertain abdominal pain, because only early diagnosis can improve prognosis. Measurement of serum lactate is diagnostically helpful, although not proving. In case of elevated lactate levels and uncertain abdominal symptoms angiography of the mesenteric vessels should be performed early. At operation, blood flow in the mesenteric arteries should be restored whenever possible.     

Epidemiology of immediate and early trauma deaths at an urban Level I trauma center

The objective of this study is to identify and differentiate the injury patterns and causes of death among patients who died within the 1st hour and those in the period between 1 and 48 hours after hospital admission. Information was collected from the 1994 to 1996 trauma data base at an urban Level I trauma center. The records of 155 trauma patients who died within the 1st hour (immediate trauma death, ITD) and between 1 and 48 hours (early trauma death, ETD) were examined retrospectively. Total and constituent Injury Severity Score (ISS), Trauma Score (TS), and Glasgow Coma Score were analyzed. ITDs constituted 49 per cent of all deaths within 48 hours. Blunt mechanisms accounted for 37 per cent of ITDs and 40 per cent of ETDs (not significant), whereas penetrating trauma accounted for 59 per cent of ITDs and 56 per cent of ETDs (not significant). Exsanguination most commonly caused death among ITDs (54%) and head injury (51%) among ETDs (P < 0.01). Patients who died within the 1st hour had higher ISS (42.6 +/- 23.2, P < 0.03), lower TS (1.7 +/- 1.9, P < 0.0001), and lower Glasgow Coma Score (3.1 +/- 1.1, P < 0.0001) than those who died after the 1st hour. Patients with ITD had a significantly worse chest ISS than those with ETD (47.4 +/- 28.6 vs 19.0 +/- 19.1, P < 0.0001). We conclude that 1) ITD is caused primarily by exsanguination, whereas ETD is largely due to the sequelae of severe neurologic injury; 2) ITD has a significantly lower TS and higher ISS than ETD; and 3) thoracic injuries are more severe among patients with ITDs than among those with ETDs. The severity of thoracic injury among ITDs suggests that rapid surgical intervention is critical during the resuscitation of these severely injured patients.     

The place of the high dependency unit in a modern New Zealand hospital

AIM: To describe the concept of, and the benefits which come from having, a high dependency unit (HDU), based on the 24 years experience of Waikato Hospital. DESCRIPTION: The HDU (9 beds/1600 patients per year) is part of the Critical Care Unit which also contains an adult intensive care unit (ICU) (11 beds/1000 patients per year), and a paediatric ICU/HDU (3 beds/250 patients per year). The regular care in the HDU is given by the specialist teams, aided by input from the ICU team. Over three years, 4390 patients were admitted having an average stay of 34 hours (61% < 24 hours). Forty eight percent of patients were over 60 years of age. The main sources of admissions were the theatre (66%), emergency department (18%), ICU (14%) and wards (11%). The main destinations were the wards (92%) and ICU (4%), with a mortality of 0.6%. The reasons for admission, specialist teams and post-operative diagnoses are described. Clinicians value the area highly, and have used it extensively. The average cost was $NZ800 per day. CONCLUSIONS: Large hospitals in New Zealand should be planning an HDU to allow adequate care for those patients too complicated for the ward but not needing the ICU. Smaller hospitals can usefully combine the functions of ICU and HDU within one area.