Sequential use of noninvasive pressure support ventilation for acute exacerbations of COPD

OBJECTIVES: To compare the efficacy of noninvasive pressure support ventilation (NIPSV) in acute decompensation in chronic obstructive pulmonary disease (COPD) by means of a bi-level positive airway pressure support system (BiPAP) in a sequential mode with medical therapy alone; to assess the short-term physiologic effects of the device on gas exchange; and to compare patients successfully ventilated with NIPSV with those in whom NIPSV failed. DESIGN: A prospective case series with historically matched control study. SETTING: A general intensive care unit (ICU) of a university hospital. PATIENTS: We evaluated the efficacy of administration of NIPSV in 42 COPD patients and compared this with standard treatment in 42 matched historical control COPD patients. INTERVENTIONS: NIPSV was performed in a sequential mode, i.e., BiPAP in the spontaneous mode was used for at least 30 min every 3 h. Between periods of ventilation, patients could be systematically returned to BiPAP when the arterial oxygen saturation was < 0.85 or when the respiratory rate was > 30 breaths/min. MEASUREMENTS AND RESULTS: Success rate, mortality, duration of ventilatory assistance, and length of ICU stay were recorded. Eleven of the 42 patients (26%) in the NIPSV group needed tracheal intubation compared with 30 of the 42 control patients (71%). The 31 patients in whom NIPSV was successful were ventilated for a mean of 6 +/- 3 days. In-hospital mortality was not significantly different in the treated versus the control group, but the duration of ventilatory assistance (7 +/- 4 days vs 15 +/- 10 days, p < 0.01) and the length of ICU stay (9 +/- 4 days vs 21 +/- 12, p < 0.01) were both shortened by NIPSV. BiPAP was effective in correcting gas exchange abnormalities. The pH values, measured after 45 min of BiPAP with optimal settings, in the success (7.38 +/- 0.04) and failure (7.28 +/- 0.04) patients were significantly different (p < 0.05). CONCLUSIONS: NIPSV, performed with a sequential mode, may be used in the management of patients with acute exacerbations of COPD.     

Chronic myelogenous leukaemia CD34+ cells exit G0/G1 phases of cell cycle more rapidly than normal marrow CD34+ cells

STUDY OBJECTIVE: To determine the safety and cost-effectiveness of mechanical ventilation with an extended-use hygroscopic condenser humidifier (Duration; Nellcor Puritan-Bennett; Eden Prairie, Minn) compared with mechanical ventilation with heated-water humidification. DESIGN: Prospective randomized clinical trial. SETTING: Medical and surgical ICUs of Barnes-Jewish Hospital, St. Louis, a university-affiliated teaching hospital. PATIENTS: Three hundred ten consecutive qualified patients undergoing mechanical ventilation. INTERVENTIONS: Patients requiring mechanical ventilation were randomly assigned to receive humidification with either an extended-use hygroscopic condenser humidifier (for up to the first 7 days of mechanical ventilation) or heated-water humidification. MEASUREMENTS: Occurrence of ventilator-associated pneumonia, endotracheal tube occlusion, duration of mechanical ventilation, lengths of intensive care and hospitalization, acquired multiorgan dysfunction, and hospital mortality. RESULTS: One hundred sixty-three patients were randomly assigned to receive humidification with an extended-use hygroscopic condenser humidifier, and 147 patients were randomly assigned to receive heated-water humidification. The two groups were similar at the time of randomization with regard to demographic characteristics, ICU admission diagnoses, and severity of illness. Risk factors for the development of ventilator-associated pneumonia were also similar during the study period for both treatment groups. Ventilator-associated pneumonia was seen in 15 (9.2%) patients receiving humidification with an extended-use hygroscopic condenser humidifier and in 15 (10.2%) patients receiving heated-water humidification (relative risk, 0.90; 95% confidence interval=0.46 to 1.78; p=0.766). No statistically significant differences for hospital mortality, duration of mechanical ventilation, lengths of stay in the hospital ICU, or acquired organ system derangements were found between the two treatment groups. No episode of endotracheal tube occlusion occurred during the study period in either treatment group. The total cost of providing humidification was $2,605 for patients receiving a hygroscopic condenser humidifier compared with $5,625 for patients receiving heated-water humidification. CONCLUSION: Our findings suggest that the initial application of an extended-use hygroscopic condenser humidifier is a safe and more cost-effective method of providing humidification to patients requiring mechanical ventilation compared with heated-water humidification.     

Lack of effects of recombinant growth hormone on muscle function in patients requiring prolonged mechanical ventilation: a prospective, randomized, controlled study

OBJECTIVE: To evaluate the benefit of recombinant human growth hormone administration on muscle strength and duration of weaning in critically ill patients undergoing prolonged mechanical ventilation. DESIGN: Prospective, randomized, controlled, single-blind study. SETTING: Intensive care unit. Patients: Twenty patients requiring > or = 7 days of mechanical ventilation for acute respiratory failure. INTERVENTION: Random assignment to receive either 0.43 IU (approximately 0.14 mg) recombinant growth hormone/kg body weight/day (treated group), or saline (nontreated group) for 12 days. MEASUREMENTS AND MAIN RESULTS: Nutritional support was guided by indirect calorimetry. Cumulative nitrogen balance was positive throughout the study period in the treated group 17.3 (44.9 +/- 17.3[SEM] g/12 days) vs. the nontreated group (-65.8 +/- 11.8 g/12 days) (p<.0001). Despite similar initial plasma concentrations, recombinant growth hormone supplementation resulted in marked increases in growth hormone, insulin like growth factor-1, and insulin concentrations (p<.05, .02, and .0001, respectively, vs. nontreated group). Body impedance determined net fat-free mass increased in the treated group (0.8 +/- 0.6 kg) vs. the nontreated group (-1.1 +/- O.5 kg) (p<.03). Initial peripheral muscle function, assessed by computer-controlled electrical stimulation of the adductor pollicis, was similarly lower in treated and nontreated groups than sex and age-matched normal controls, and decreased further during the study period. Arterial blood gases, cumulative total mechanical ventilation time, and number of hrs/day of mechanical ventilation during weaning were similar in both patient groups. Only three of the ten patients in each group were weaned from mechanical ventilation by day 12. CONCLUSIONS: Daily administration of recombinant growth hormone in mechanically ventilated patients with acute respiratory failure promotes a marked nitrogen retention. However, this reaction is accompanied neither by an improvement in muscle strength nor by a shorter duration of ventilatory supports.     

PSA screening--current controversy

OBJECTIVE: To evaluate treatment with noninvasive ventilation (NIV) by nasal mask as an alternative to endotracheal intubation and conventional mechanical ventilation in patients with hematologic malignancies complicated by acute respiratory failure to decrease the risk of hemorrhagic complications and increase clinical tolerance. DESIGN: Prospective clinical study. SETTING: Hematologic and general intensive care unit (ICU), University of Rome "La Sapienza". PATIENTS: 16 consecutive patients with acute respiratory failure complicating hematologic malignancies. INTERVENTIONS: NIV was delivered via nasal mask by means of a BiPAP ventilator (Respironics, USA); we evaluated the effects on blood gases, respiratory rate, and hemodynamics along with tolerance, complications, and outcome. MEASUREMENTS AND RESULTS: 15 of the 16 patients showed a significant improvement in blood gases and respiratory rate within the first 24 h of treatment. Arterial oxygen tension (PaO2), PaO2/FIO2 (fractional inspired oxygen) ratio, and arterial oxygen saturation significantly improved after 1 h of treatment (43+/-10 vs 88+/-37 mmHg; 87+/-22 vs 175+/-64; 81+/-9 vs 95+/-4%, respectively) and continued to improve in the following 24 h (p < 0.01). Five patients died in the ICU following complications independent of the respiratory failure, while 11 were discharged from the ICU in stable condition after a mean stay of 4.3+/-2.4 days and were discharged in good condition from the hospital. CONCLUSIONS: NIV by nasal mask proved to be feasible and appropriate for the treatment of respiratory failure in hematologic patients who were at high risk of intubation-related complications.     

Does N-acetyl-L-cysteine influence cytokine response during early human septic shock?

STUDY OBJECTIVE: To assess the effects of adjunctive treatment with N-acetyl-L-cysteine (NAC) on hemodynamics, oxygen transport variables, and plasma levels of cytokines in patients with septic shock. DESIGN: Prospective, randomized, double-blind, placebo-controlled study. SETTING: A 24-bed medicosurgical ICU in a university hospital. PATIENTS: Twenty-two patients included within 4 h of diagnosis of septic shock. INTERVENTIONS: Patients were randomly allocated to receive either NAC (150 mg/kg bolus, followed by a continuous infusion of 50 mg/kg over 4 h; n= 12) or placebo (n=10) in addition to standard therapy. MEASUREMENTS: Plasma concentrations of tumor necrosis factor-alpha (TNF), interleukin (IL)-6, IL-8, IL-10, and soluble tumor necrosis factor-alpha receptor-p55 (sTNFR-p55) were measured by sensitive immunoassays at 0, 2, 4, 6 and 24 h. Pulmonary artery catheter-derived hemodynamics, blood gases, hemoglobin, and arterial lactate were measured at baseline, after infusion (4 h), and at 24 h. RESULTS: NAC improved oxygenation (PaO2/FIO2 ratio, 214+/-97 vs 123+/-86; p<0.05) and static lung compliance (44+/-11 vs 31+/-6 L/cm H2O; p<0.05) at 24 h. NAC had no significant effects on plasma TNF, IL-6, or IL-10 levels, but acutely decreased IL-8 and sTNFR-p55 levels. The administration of NAC had no significant effect on systemic and pulmonary hemodynamics, oxygen delivery, and oxygen consumption. Mortality was similar in both groups (control, 40%; NAC, 42%) but survivors who received NAC had shorter ventilator requirement (7+/-2 days vs 20+/-7 days; p<0.05) and were discharged earlier from the ICU (13+/-2 days vs 32+/-9 days; p<0.05). CONCLUSION: In this small cohort of patients with early septic shock, short-term IV infusion of NAC was well-tolerated, improved respiratory function, and shortened ICU stay in survivors. The attenuated production of IL-8, a potential mediator of septic lung injury, may have contributed to the lung-protective effects of NAC.     

Comparison of noninvasive positive pressure ventilation with standard medical therapy in hypercapnic acute respiratory failure

STUDY OBJECTIVE: To compare the efficacy of standard medical therapy (ST) and noninvasive mechanical ventilation additional to standard medical therapy in hypercapnic acute respiratory failure (HARF). DESIGN: Single center, prospective, randomized, controlled study. SETTING: Pulmonary medicine directed critical care unit in a university hospital. PATIENTS: Between March 1993 and November 1996, 30 HARF patients were randomized to receive ST or noninvasive positive pressure ventilation (NPPV) in addition to ST. INTERVENTIONS: NPPV was given with an air-cushioned face via a mechanical ventilator (Puritan Bennett 7200) with initial setting of 5 cm H2O continuous positive airway pressure and 15 cm H2O pressure support. RESULTS: At the time of randomization, patients in the ST group had (mean+/-SD) PaO2 of 54+/-13 mm Hg, PaCO2 of 67+/-11 mm Hg, pH of 7.28+/-0.02, and respiratory rate of 35.0+/-5.8 breaths/min. Patients in the NPPV group had PaO2 of 55+/-14, PaCO2 of 69+/-15, pH of 7.27+/-0.07, and respiratory rate of 34.0+/-8.1 breaths/min. With ST, there was significant improvement of only respiratory rate (p < 0.05). However, with NPPV, PaO2 (p < 0.001), PaCO2 (p < 0.001), pH (p < 0.001), and respiratory rate (p < 0.001) improved significantly compared with baseline. Six hours after randomization, pH (p < 0.01) and respiratory rate (p < 0.01) in NPPV patients were significantly better than with ST. Hospital stay for NPPV vs ST patients was, respectively, 11.7+/-3.5 and 14.6+/-4.7 days (p < 0.05). One patient in the NPPV group required invasive mechanical ventilation. The conditions of six patients in the ST group deteriorated and they were switched to NPPV; this was successful in four patients, two failures were invasively ventilated. CONCLUSION: This study suggests that early application of NPPV in HARF patients facilitates improvement, decreases need for invasive mechanical ventilation, and decreases the duration of hospitalization.     

High survival rate in 122 ARDS patients managed according to a clinical algorithm including extracorporeal membrane oxygenation

OBJECTIVE: We investigated whether a treatment according to a clinical algorithm could improve the low survival rates in acute respiratory distress syndrome (ARDS). DESIGN: Uncontrolled prospective trial. SETTING: One university hospital intensive care department. PATIENTS AND PARTICIPANTS: 122 patients with ARDS, consecutively admitted to the ICU. INTERVENTIONS: ARDS was treated according to a criteria-defined clinical algorithm. The algorithm distinguished two main treatment groups: The AT-sine-ECMO (advanced treatment without extracorporeal membrane oxygenation) groups (n = 73) received a treatment consisting of a set of advanced non-invasive treatment options, the ECMO treatment group (n = 49) received additional extracorporeal membrane oxygenation (ECMO) using heparin-coated systems. MEASUREMENTS AND RESULTS: The groups differed in both APACHE II (16 +/- 5 vs 18 +/- 5 points, p = 0.01) and Murray scores (3.2 +/- 0.3 vs 3.4 +/- 0.3 points, p = 0.0001), the duration of mechanical ventilation prior to admission (10 +/- 9 vs 13 +/- 9 days, p = 0.0151), and length of ICU stay in Berlin (31 +/- 17 vs 50 +/- 36 days, p = 0.0016). Initial PaO2/FIO2 was 86 +/- 27 mm Hg in AT-sine-ECMO patients that improved to 165 +/- 107 mm Hg on ICU day 1, while ECMO patients showed an initial PaO2/FIO2 of 67 +/- 28 mm Hg and improvement to 160 +/- 102 mm Hg was not reached until ICU day 13. QS/QT was significantly higher in the ECMO-treated group and exceeded 50% during the first 14 ICU days. The overall survival rate in our 122 ARDS patients was 75%. Survival rates were 89% in the AT-sine ECMO group and 55% in the ECMO treatment group (p = 0.0000). CONCLUSIONS: We conclude that patients with ARDS can be successfully treated with the clinical algorithm and high survival rates can be achieved.     

Randomized multicenter trial comparing synchronized and conventional intermittent mandatory ventilation in neonates

OBJECTIVE: To compare synchronized intermittent mandatory ventilation (SIMV) and conventional intermittent mandatory ventilation (IMV) in neonates. STUDY DESIGN: Prospective, multicenter, randomized clinical trial. SETTING: Level III neonatal intensive care units at six university or children's hospitals. PATIENTS: Three hundred twenty-seven infants receiving conventional IMV for respiratory distress syndrome, pneumonia, or meconium aspiration pneumonitis were randomly assigned a 7.5 +/- 6 hours of age to either continue with IMV or change to SIMV. Infants assigned to each mode of ventilation had similar birth weight (BW), gestational age, and Apgar scores at birth, and similar oxygenation indexes at randomization. They received similar surfactant therapy and had similar incidence of sepsis, seizures, secondary pneumonia, and necrotizing enterocolitis. In the infants with BW less than 1000 gm, more infants receiving IMV had surgical ligation of their patent ductus arteriosus than did those receiving SIMV (27 vs. 7 %; p = 0.02). ANALYSIS: Data was analyzed overall for all infants and also separately within three BW groups: less than 1000 gm, 1000 to 2000 gm, and more than 2000 gm. The 1000 to 2000 gm BW group was further analyzed in subgroups weighing 1000 to 1499 gm and 1500 to 2000 gm. RESULTS: In all infants, at 1 hour after randomization, the infants receiving SIMV had a lower mean airway pressure than those receiving IMV (8.08 +/- 2.15 vs. 8.63 +/- 2.59; p<0.05), with similar fractions of inspired oxygen and oxygenation indexes. Infants whose BW was 1000 to 2000 gm at 0.5 hour required a lower fraction of inspired oxygen with SIMV than with IMV (0.52 +/- 0.20 vs. 0.62 +/- 0.27; p<0.05) and had better oxygenation at 1 hour, as shown by lower oxygenation indexes with SIMV than with IMV (6.14 +/- 4.17 vs. 9.42 +/- 8.41; p = 0.01). Infants whose BW was 1000 to 2000 gm received a lower number of unit doses of sedative/analgesic drugs per infant during the first 4 days of SIMV than did infants receiving IMV (3.8 +/- 3.4 vs 6.3 +/- 5.5 unit doses; p = 0.02). Infants whose BW was more than 2000 gm had a shorter duration of mechanical ventilation with SIMV than with IMV (median, 72 vs 93 hours; p = 0.02). Three of the forty-six infants receiving IMV but none of the 47 infants receiving SIMV required extracorporeal membrane oxygenation. In the infants with BW less than 1000 gm, fewer infants treated with SIMV required supplemental oxygen at 36 weeks of postconceptional age than did those treated with IMV (47 vs 72%; p<0.05). In 83 infants whose lungs were mechanically ventilated for 14 days or longer, all with BW less than 2000 gm, those treated with SIMV regained their BW earlier than those treated with IMV (median, 21.5 vs 29 days; p<0.01). There were no differences in the rates of death, intraventricular hemorrhage (grades III and IV), air leak, need for pharmacologic paralysis, or need for supplemental oxygen at 28 days. CONCLUSIONS: We found that SIMV was at least as efficacious as conventional IMV, and may have improved certain outcomes in BW-specific groups.     

Indications of planned sedation following intracranial neurosurgery. Prospective study of decisional criteria

General Anaesthesia (GA) is usually stopped early after intracranial surgery. An impaired neurological status or surgical difficulties may lead to sedate some patients (pts) in the intensive care unit (ICU). The aims of the study were to establish and to evaluate predictive criteria for post- operative sedation. In one group (G1), GA and mechanical ventilation (MV) were discontinued early after surgery and pts stayed at least 12 h. in the ICU. In the other group (G2), sedation and MV were prolonged 24 h., until a clinical and scannographic evaluation. Thereafter, sedation was discontinued or prolonged according to both surgical and anesthetic considerations. These criteria were established according to the literature and to local practices. Before surgery, they depended on clinical status, radiological data and etiology; during surgery, on surgical and medical semiology and difficulties or incidents during the procedure. Adult pts undergoing intracranial surgery under GA were consecutively included in a 6 months prospective study. Patients suffering acute head trauma, pre operative coma (Glasgow CS < 8) or extraneurologic disease (responsible for delayed MV weaning) were not included. Sedation was performed with midazolamR (.05-.15 mg.kg-1.h-1) + phenoperidineR without myorelaxation. The ideal level of sedation was established as defined by Boeke. One hundred and ninety five pts (80 f; 49 +/- 15y-o) were included (G1 = 130, G2 = 65). Surgical indications were: malignant tumor = 61, meningioma = 50, vascular disease = 53, other = 31. ICU stay lasted 5.6 +/- 8 d and MV 3.7 +/- 7 d.(ABSTRACT TRUNCATED AT 250 WORDS)     

Atrial natriuretic factor modifies the biosynthesis and turnover of norepinephrine in the rat adrenal medulla

Abnormalities of the cornea and conjunctiva occur in association with neurological diseases, nocturnal lagophthalmos, coma, infection, and mechanical ventilation. We investigated the incidence and causes of ocular surface disorders in critically ill patients. In a retrospective study, the presence of conjunctivitis and corneal erosion was determined by reviewing the medical charts of 143 mechanically ventilated patients (intensive care unit [ICU] stay > or =7 days). In the subsequent prospective study, 15 patients who had sedatives or muscle relaxants administered continuously for more than 48 h in the ICU were investigated. Corneal erosion was examined using a slit lamp once a day. Ocular surface disorder was found in 28 of the 143 patients (20%) whose ICU stay exceeded 7 days. The incidence increased with continuous sedation (35% vs 15%). The incidence also increased with continuous neuromuscular blockade (39% vs 11%). In the prospective study, nine patients (60%) developed corneal erosion. A patient's inability to fully close his or her eyes increased the incidence (P < 0.01) of corneal erosion. Protective eyelid taping was effective in preventing and treating the corneal erosion. In conclusion, the critically ill often develop ocular surface disorders, especially when sedated and immobilized. A close relationship was observed between these conditions and the inability to close one's eyes.     

The sedative and analgesic sparing effect of music

BACKGROUND: To determine whether music influences intraoperative sedative and analgesic requirements, two randomized controlled trials were performed. METHODS: In phase 1, 35 adults undergoing urologic procedures with spinal anesthesia and patient-controlled intravenous propofol sedation were randomly assigned to hear favorable intraoperative music via headset or to have no music. In phase 2, 43 adults undergoing lithotripsy treatment of renal or ureteral calculi and receiving patient-controlled intravenous opioid analgesia were randomly assigned to either a music or no-music group. The effect of music on sedatives and analgesics requirements, recovery room duration, and adverse outcomes was assessed. RESULTS: In phase 1, patients in the music group required significantly less propofol for sedation than patients in the control group (0 [0-150] mg vs. 90 [0-240] mg, median[range]; P < 0.001). These findings persisted after adjusting for duration of surgery (0.3+/-0.1 mg/min vs. 1.6+/-0.4 mg/min; P < 0.001). Similarly, in phase 2, patients who listened to music had a significant reduction in alfentanil requirements (1,600 [0-4,250] microg vs. 3,900 [0-7,200] microg; P = 0.005). This persisted after adjusting for duration of surgery (52+/-9 microg/min vs. 119 +/-16 microg/min, mean +/- SD, P < 0.001). Duration of stay in the postanesthesia care unit and the rate of adverse events was similar in both groups (P = NS). CONCLUSIONS: Use of intraoperative music in awake patients decreases patient-controlled sedative and analgesic requirements. It should be noted, however, that patients in the no-music group did not use a headset during operation. Thus, the decrease in sedative and analgesic requirements could be caused by elimination of ambient operating room noise and not by the effects of music.     

Comparison of neuromuscular effects, efficacy and safety of rocuronium and atracurium in ambulatory anaesthesia

PURPOSE: To compare the neuromuscular effects, efficacy, and safety of equi-effective doses of rocuronium and atracurium in ambulatory female patients undergoing surgery. METHODS: Forty-one patients undergoing laparoscopic gynaecological surgery were randomized to receive 2 X ED90 rocuronium (0.6 mg.kg-1; n = 20) or atracurium (0.5 mg.kg-1; n = 21) during intravenous propofol/alfentanil anaesthesia with N2O/O2 ventilation. Neuromuscular block was measured with a mechanomyogram eliciting a train-of-four (TOF) response at the wrist. Intubation conditions 60 sec after administration of muscle relaxant and immediate cardiovascular disturbances or adverse events during the hospital stay were noted by blinded observers. RESULTS: Compared with atracurium, rocuronium was associated with a shorter onset time (59.0 +/- 22.2 vs 98.6 +/- 41.4 sec; P < 0.001) and clinical duration of action (33.3 +/- 7.1 vs 44.7 +/- 7.2 min; P < 0.001), but longer spontaneous recovery index (9.6 +/- 2.41 vs 6.9 +/- 1.89 min; P = 0.023) and a similar time to spontaneous recovery to TOF 70%; 53 +/- 6.31 vs 59.2 +/- 7.59 min; P = 0.139). Tracheal intubation was accomplished in < 90 sec in all patients receiving rocuronium but in only 14 of 21 patients receiving atracurium. The incidence of adverse events and the cardiovascular profiles for the two drugs were similar, although one patient receiving atracurium experienced transient flushing of the head and neck. CONCLUSION: Rocuronium has minimal side effects, provides conditions more suitable for rapid tracheal intubation, and is associated with a shorter clinical duration than atracurium. Once begun, the spontaneous recovery profile of rocuronium is slightly slower than that of atracurium.     

The use of noninvasive positive pressure ventilation in the emergency department: results of a randomized clinical trial

OBJECTIVE: To determine whether the use of noninvasive positive pressure ventilation (NPPV) in the emergency department (ED) will reduce the need for tracheal intubation and mechanical ventilation. DESIGN: Randomized, controlled, prospective clinical trial. SETTING: ED of Barnes-Jewish Hospital, a university-affiliated teaching hospital. PATIENTS: Twenty-seven patients meeting a predetermined definition of acute respiratory distress requiring hospital admission. INTERVENTIONS: Conventional medical therapy for the various etiologies of acute respiratory distress and the application of NPPV. MEASUREMENTS AND RESULTS: The primary outcome measure was the need for tracheal intubation and mechanical ventilation. Secondary outcomes also assessed included hospital mortality, hospital length of stay, acquired organ system derangements, and the utilization of respiratory care personnel. Sixteen patients (59.3%) were randomly assigned to receive conventional medical therapy plus NPPV, and 11 patients (40.7%) were randomly assigned to receive conventional medical therapy without NPPV. The two groups were similar at the time of randomization in the ED with regard to demographic characteristics, hospital admission diagnoses, and severity of illness. Tracheal intubation and mechanical ventilation was required in seven patients (43.8%) receiving conventional medical therapy plus NPPV and in five patients (45.5%) receiving conventional medical therapy alone (relative risk=0.96; 95% confidence interval=0.41 to 2.26; p=0.930). There was a trend towards a greater hospital mortality rate among patients in the NPPV group (25%) compared to patients in the conventional medical therapy group (0.0%) (p=0.123). Among patients who subsequently required mechanical ventilation, those in the NPPV group had a longer time interval from ED arrival to the start of mechanical ventilation compared to patients in the conventional medical therapy group (26.0+/-27.0 h vs 4.8+/-6.9 h; p=0.055). CONCLUSIONS: We conclude that the application of NPPV in the ED may delay tracheal intubation and the initiation of mechanical ventilation in some patients with acute respiratory distress. We also demonstrated that the application of NPPV was associated with an increased hospital mortality rate. Based on these preliminary observations, larger clinical investigations are required to determine if adverse patient outcomes can be attributed to the early application of NPPV in the ED. Additionally, improved patient selection criteria for the optimal administration of NPPV in the ED need to be developed.     

Change in anaesthesia practice and postoperative sedation shortens ICU and hospital length of stay following coronary artery bypass surgery

We randomized prospectively 144 patients, undergoing elective coronary artery bypass surgery, to either early or to routine extubation [mechanical ventilatory support for 4-7 h (Group A), or 8-14 h (Group B)]. Anaesthesia was modified for both groups. The groups were well matched in terms of sex, age, NYHA class, preoperative left ventricular ejection fraction, bypass time and aortic cross-clamp time, number of grafts used, and blood units transfused. All patients had normal preoperative respiratory, renal, hepatic and cerebral functions. Mechanical ventilatory support (mean +/- SD) was 6.3 +/- 0.7 h for Group A and 11.6 +/- 1.3 h for Group B. Mean ICU stay was 17 +/- 1.3 h for Group A and 22 +/- 1.2 h for Group B, while the mean hospital stay was 7.3 +/- 0.8 days and 8.4 +/- 0.9, respectively. There were no statistically significant differences in the frequency of all postoperative complications among the two groups. There were no reintubation, readmission to the ICU or death in either group. We concluded that change in anaesthesia practice and early postoperative sedation in patients undergoing elective coronary artery bypass graft (CABG) surgery resulted in earlier tracheal extubation, shorter ICU and hospital length of stay without organ dysfunction or postoperative complications. Early extubation was only possible due to the modification of anaesthesia and ICU sedation regime.     

Venous leg ulcers. Part 1: Aetiology

Cardiogenic pulmonary edema is a frequent cause of reparatory failure. We investigated the effects of nasal continuous positive airway pressure (CPAP) in patients with severe pulmonary edema associated with acute myocardial infarction. Twenty-nine consecutive patients were divided into 3 groups: firstly, 7 intubated patients who received mechanical ventilation at study entry comprised the intubation group. The rest of the patients were randomly assigned to either of the following 2 groups: 11 patients who received oxygen plus CPAP delivered by a nasal mask (CPAP group), and 11 patients who received oxygen only via face mask (oxygen group). All patients in the intubation group had cardiogenic shock. Two patients (18%) in the CPAP group and 8 patients (73%) in the oxygen group required mechanical ventilation with endotracheal intubation (p=0.03). The hospital mortality rate in the CPAP group (9%) was significantly lower than the oxygen group (64%, p=0.02). The pulmonary artery wedge pressure and heart rate were significantly lower in the CPAP group than in the oxygen group 24 h after study entry (p<0.05 and p<0.01). The mean pulmonary artery pressure 48 h after study entry was 18+/-5 mmHg in the CPAP group and 25+/-8 mmHg in the oxygen group (p<0.05). The PaO2/FiO2 ratio increased in the intubation group (168+/-69 to 240+/-57, p<0.05) and the CPAP group (137+/-17 to 253+/-67, p<0.01) 24 h after study entry. Arterial plasma endothelin-1 concentrations decreased significantly earlier in the CPAP group than in the oxygen group (p<0.05). In patients without cardiogenic shock, nasal CPAP lead to an early improvement in oxygenation and hemodynamics, and decreased the mortality rate. Early and active respiratory management is recommended in patients with pulmonary edema associated with acute myocardial infarction.     

Bone mineral density in pediatric patients with idiopathic hypercalciuria

Between October 1993 and April 1995, a total of 77 neonates requiring mechanical ventilation were enrolled in this study and were randomly divided into two groups. Group A consisted of 31 premature infants (mean birthweight 1.36 +/- 0.29 kg) with respiratory distress syndrome (RDS) and seven neonates (mean birthweight 3.2 +/- 0.5 kg) with meconium aspiration syndrome (MAS). Group B consisted of 31 premature infants (mean birthweight 1.31 +/- 0.3 kg) with RDS and eight neonates (mean birthweight 3.3 +/- 0.5 kg) with MAS. Infants in group A received synchronized intermittent mandatory ventilation (SIMV) and infants in group B received conventional intermittent mandatory ventilation (CIMV) therapy. In premature infants with RDS, our data showed: (i) the duration of ventilation was significantly shorter (P < 0.05) in the synchronized group (156 +/- 122 h) compared to the conventional group (242 +/- 175 h); (ii) significantly fewer (P < 0.05) patients required reintubation in the synchronized group than in the conventional group (three vs 11 patients); (iii) incidence of severe intraventricular hemorrhage (grades 3 and 4) was significantly lower (P < 0.05) in the synchronized group compared to the conventional group (one vs seven patients); (iv) incidence of bronchopulmonary dysplasia was significantly lower (P < 0.05) in the synchronized group than in the control group (one vs seven patients). In neonates with MAS, our data showed no significant difference (P < 0.05) on duration of ventilation, incidence of reintubation, incidence of pneumothorax or mortality rate between synchronized and control groups.     

N-Glycosylation affects endoplasmic reticulum degradation of a mutated derivative of carboxypeptidase yscY in yeast

BACKGROUND: Reports of short- and medium-term evolution of Lung Function Tests (LFT) in infants with bronchopulmonary dysplasia (BPD) are still scarce. POPULATION AND METHODS: The results of the first (before 3 months of corrected age) and the second (between 3 and 9 months of corrected age) LFT in 22 premature infants with BPD (gestational age 31 +/- 2.5 weeks; birth weight: 1570 +/- 440 g; duration of mechanical ventilation: 46 +/- 24 days, total duration of oxygen therapy: 88 +/- 47 days) were compared to those obtained in 27 normal infants for the first LEF and 10 normal infants for the second LFT, similar to the patients for birth weight and corporeal index (CI). RESULTS: In the first LFT, major abnormalities were an increased thoracic gaz volume (TGV) (16.5 +/- 42 vs 122 +/- 24 mL; P < 0.001) and TGV CI ratio (1.25 +/- 0.31 vs 0.89 +/- 0.17 ml/kg/m2; P < 0.0001) a decreased pulmonary compliance (2.49 +/- 1.46 vs 11.60 +/- 4.50 mL/cmH2O; P < 0.0001) and specific pulmonary compliance (0.015 +/- 0.10 vs 0.100 +/- 0.042 mL/cmH2O/mL de TGV; P < 0.0001), an increased total pulmonary resistance (20.4 +/- 12.1 vs 10.5 +/- 5.3 cmH2O/L/s; P < 0.001). In the second LFT, an increased TGV (235 +/- 62 vs 166 +/- 28 mL; P < 0.01) and TGV CI ratio (1.64 +/- 0.65 vs 0.98 +/- 0.11 ml/kg/m2; P < 0.05), a decreased pulmonary compliance (2.68 +/- 2.0 vs 15.2 +/- 5.7 mL/cmH2O; P < 0.0001) and specific pulmonary compliance (0.013 +/- 0.010 vs 0.106 +/- 0.050 mL/cmH2O/mL de TGV; P < 0.0001), an increased total pulmonary resistance (17.1 +/- 9.6 vs 8.6 +/- 4.9 cmH2O/L/s; P < 0.05) were noted when compared with the control group results. Major abnormalities of the blood gases were hypoxemia (63 +/- 10 vs 85 +/- 20 mmHg; P < 0.05), hypercapnia (38.5 vs 31 +/- 4 mmHg; P < 0.0001) during the first LFT. Hypoxemia (77 +/- 14 vs 90 +/- 14 mmHg and hypercapnia (37 +/- 4 vs 29 +/- 5 mmHg) continued in the second LFT. Thoracic distention and total pulmonary resistances in infants with BPD did not improve but their pulmonary compliance (P < 0.0001) and PaO2 (P < 0.01) between the first and second LFT did it. Infants who had been ventilated for a hyaline membrane disease (HMD) were more hypoxic on the second LFT (P < 0.05) than those who had been ventilated for other causes. Statistically significant relationships were found between thoracic distention and duration of positive inspiratory pressure (P < 0.05; r = 0.43), duration of positive expiratory pressure (P < 0.05, r = 0.45) total oxygen therapy duration; between total pulmonary resistance and duration of mechanical ventilation with high frequency (P < 0.05; r = 0.52); between hypoxemia and duration of oxygen therapy with FiO2 > or = 60% (P < 0.05; r = 0.54). CONCLUSIONS: This study shows prolonged clinical and functional abnormalities of the respiratory functions requiring longer follow-up.     

Prediction of spinal cord ischemia with a retrievable stent graft on endovascular treatment for a case of thoracic aortic aneurysm

OBJECTIVE: To determine the pharmacokinetics and absolute bioavailability of ciprofloxacin in 12 critically ill patients receiving continuous enteral feeding. Design: a prospective, cross-over study. SETTING: 12-bed surgical intensive care unit in a University Hospital. PATIENTS: 12 stable critically ill patients on mechanical ventilation and receiving continuous enteral feeding (Normoreal fibres) without diarrhea or excessive residual gastric contents ( < 200 ml/4 h). None had gastro-intestinal disease, renal insufficiency (estimated creatinine clearance > or = 50 ml/min) or was receiving medications that could interfere with ciprofloxacin absorption or metabolism. MEASUREMENTS AND MAIN RESULTS: The study was carried out after the fourth (steady state) b. i. d. intravenous (i. v.) 1-h infusion of 400 mg and the second b. i. d. nasogastric (NG) dose of 750 mg (crushed tablet in suspension). Plasma concentrations were measured by high-performance liquid chromatography. The median (range) peak concentration after i. v. infusion was 4.1 (1.5-7.4) mg/l, and that after NG administration was 2.3 (0.7-5.8) mg/l, occurring 1.25 (0.75-3.33) h after dosing. The median [range] areas under plasma concentration-time curves were similar for the two administration routes (10.3 [3.3-34.6] and 8.4 [3.6-53.4] for i.v. infusion and NG administration, respectively). Ciprofloxacin bioavailability ranges from 31 to 82 % (median, 44%). CONCLUSIONS: In tube-fed critically ill patients, a switch to the NG ciprofloxacin after initial i. v. therapy to simplify the treatment of severe infections is restricted to those for whom serial assessments of ciprofloxacin levels are routinely available.     

Limitation of therapeutic activity in elderly critically ill patients. Project for the Epidemiological Analysis of Critical Care Patients

OBJECTIVE: To establish whether the age of patients admitted into the intensive care unit (ICU) influences the amount of therapy received. DESIGN: Observational, prospective, multicenter study. SETTING: Eighty-six multidisciplinary ICUs in Spain, including coronary patients. PATIENTS: The patients (n = 8,838) were studied during a 6-month period between 1992 and 1993. Patients < 16 yrs of age and patients dying within the first 6 hrs were excluded from the study. MEASUREMENTS AND MAIN RESULTS: We collected data on age, gender, type of diagnosis at the time of admission, severity level by Acute Physiology and Chronic Health Evaluation (APACHE) II and III, quality of life survey score, therapeutic activity during the first 24 hrs by Therapeutic Intervention Scoring System, and ICU and hospital mortality rates. In the sample of patients, 12.5% were > 75 yrs of age. Compared with younger patients, these patients had higher APACHE II (18.41 +/- 0.23 vs. 15.14 +/- 0.09 points, p < .001) and APACHE III (65.8 +/- 0.81 vs. 53.32 +/- 0.33 points, p < .001) scores, a higher quality of life survey score (i.e., worse quality of life, 7.19 +/- 0.19 vs. 3.86 +/- 0.05 points, p < .001), and a greater ICU mortality rate (21.9% vs. 15.3%, p < .00001) and hospital mortality rate (30.8% vs. 19.3%, p < .00001). However, patients > 75 yrs had a lower Therapeutic Intervention Scoring System score (19.83 +/- 0.28 vs. 21.17 +/- 0.12 points, p < .001). Multivariate analysis showed that once severity, need for mechanical ventilation, diagnostic group, and mortality rate were taken into account, there was less therapeutic activity in patients > 75 yrs of age. CONCLUSIONS: Patients > 75 yrs of age represent a large proportion of patients in Spanish ICUs. Although their mortality rate and severity scores were higher than those values in younger patients, patients > 75 yrs of age received less therapy.     

Level concept of analgesic dosing in intensive care medicine with sufentanil

OBJECTIVE: The efficacy of a 3-level regimen of analgesia and sedation was investigated in a clinical setting. Level 1 consisted of continuous administration of sufentanil, in level 2 continuous administration of midazolam and level 3 continuous administration of midazolam and clonidine was added according to patients' needs. METHODS: Sufentanil at 1 microgram/kg/h was given initially. Later it was adjusted to patients' requirements in accordance with the Ramsay score (group 1). Long-term intubated patients received in addition midazolam 0.05 mg/kg/h (group 2). If needed, clonidine 1 microgram/kg/h was added (group 3). Mean drug requirements were investigated during controlled ventilation and during assisted ventilation with spontaneous breathing > 25% of total minute ventilation. In group 1 arterial paCO2 was measured to estimate drug-induced respiratory depression. Values given are median and ranges. RESULTS: With the 3-level-regimen of analgesia and sedation a Ramsay score of 2-3 was achieved in all intensive-care patients. In group 1 (n = 109; 36.7%) paCO2 values were similar at all times. Patients on controlled ventilation needed sufentanil 0.6 (0.075-2.5) microgram/kg/h, on assisted ventilation 0.4 (0.05-2.5) microgram/kg/h. Patients of group 2 (n = 113; 38.1%) had on controlled ventilation a higher requirement of sufentanil 1.2 (0.09-2.7) micrograms/kg/h, in addition Midazolam 0.05 (0.002-0.56) mg/kg/h was given. On assisted ventilation with spontaneous breathing > 25% sufentanil 0.9 (0.05-2.6) microgram/kg/h plus midazolam 0.04 (0.002-0.38) mg/kg/h was sufficient. Group 3 (n = 75; 25.2%) had on controlled ventilation a higher requirement of sufentanil with 1.5 (0.09-4.0) micrograms/kg/h and midazolam 0.05 (0.005-0.52) mg/kg/h, in addition clonidine 1.1 (0.12-2.88) micrograms/kg/h was given. On assisted ventilation with spontaneous breathing > 25% requirement of sufentanil with 1.1 (0.15-2.6) micrograms/kg/h and of midazolam with 0.05 (0.002-0.22) mg/kg/h was slightly lower, whereas more clonidine was needed with 1.3 (0.12-2.88) micrograms/kg/h. CONCLUSION: Continuous infusion of sufentanil only for analgesia and sedation is suitable for intensive-care patients with a short stay in the ICU. Respiratory depression during spontaneous breathing is not significant. The supplementary administration of midazolam and clonidine according to the presented regimen was shown to be of advantage for patients with a longer stay in ICU.