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At least 19 recordsLinked to original sources
PubMed1998

Clinical characteristics, respiratory functional parameters, and outcome of a two-hour T-piece trial in patients weaning from mechanical ventilation.

The discrepancy in results from different studies regarding outcome of weaning from mechanical ventilation may be due to several factors such as the differences in patient populations and weaning indexes used. In order to analyze the clinical characteristics and weaning indexes in patients undergoing a 2-h T-piece weaning trial and the relationship between the etiology of acute respiratory failure (ARF) and the outcome of this weaning trial, we prospectively studied 217 patients receiving mechanical ventilation who met standard weaning criteria. Successful weaning occurred in 57.6% (125 of 217) of patients: 13 of 33 (39.4%) patients with chronic obstructive pulmonary disease (COPD), 27 of 46 (58.7%) neurologic patients, and 85 of 138 (61.6%) patients with ARF. Ventilatory support was reinstituted in 31.8% (69 of 217) patients: 20 of 33 (60.6%) of patients with COPD, four of 46 (8.7%) neurologic patients, and 45 of 138 (32.6%) patients with ARF (p < 0.001). Reintubation was required in 23 of 148 (15.5%) patients: 15 of 42 (35.7%) neurologic patients, and eight of 93 (8.6%) patients with ARF, whereas no patient with COPD was reintubated (p < 0.001). Using a discriminant analysis, the following variables were selected as the best predictors of outcome: (1) in the whole population, days of mechanical ventilation before weaning trial (DMV), frequency-to-tidal volume ratio (f/VT), maximal inspiratory pressure (MIP), airway occlusion pressure (P0.1), maximal expiratory pressure (MEP), and vital capacity (VC); (2) in patients with ARF, DMV, P0.1/MIP, MIP, f/VT, and age; (3) in patients with COPD, f/VT, P0.1, P0.1/MIP, MIP, age, and DMV; (4) in neurologic patients, MIP, MEP, and f/VT.P0.1. Using these predictors, 74.6% of the whole population, 76.1% of patients with ARF, 93.9% of patients with COPD, and 73.9% of neurologic patients were accurately classified as weaning successes or failures. The highest rate of reintubation occurred in neurologic patients. In this group, the ability to cough and clear respiratory secretions, objectively reflected by MEP, may help in clinical decision-making.

Acute Disease↗
PubMed1997

Prospective, randomised, multicentre study of meropenem versus imipenem/cilastatin as empiric monotherapy in severe nosocomial infections.

The clinical and bacteriological efficacy and the tolerability of meropenem versus imipenem/cilastatin (both 1 g t.i.d.) in severe nosocomial infections were compared in a multicentre, randomised, nonblinded study. A total of 151 patients were recruited; 133 (66 meropenem, 67 imipenem/cilastatin) were clinically evaluable and 84 (42 meropenem, 42 imipenem/cilastatin) bacteriologically evaluable. Most clinically evaluable patients (90%) were in intensive care units, required mechanical ventilation (72%), and had received previous antibiotic therapy (62%). The mean (+/- SD) APACHE II score was 15.2 (+/- 6.6) in the meropenem group and 17.8 (+/- 6.8) in the imipenem/cilastatin group. The primary infections were nosocomial lower respiratory tract infections (56% of patients), intra-abdominal infections (15%), septicaemia (21%), skin/skin structure infections (5%), and complicated urinary tract infections (3%); 35% of the patients had two or more infections. There was no significant difference between the meropenem and imipenem/cilastatin groups in the rates of satisfactory clinical (weighted percentage 87% vs. 74%) or bacteriological (weighted percentage 79% vs. 71%) response. There was a slightly higher rate of clinical success with meropenem against primary or secondary lower respiratory tract infection (89% vs. 76%). Drug-related adverse events occurred in 17% and 15% of meropenem and imipenem/cilastatin patients, respectively. Meropenem (1 g t.i.d.) was as efficacious as the same dose of imipenem/cilastatin in this setting, and both drugs were well tolerated.

Adolescent↗
PubMed1996

[Cranioencephalic trauma in adults: clinical and radiologic features].

BACKGROUND: To analyse extracranial complications and basic variables in head-injury patients, such as Glasgow coma score (GCS), intracranial pressure (ICP) and cranial computerized tomography (CT), in relation to the outcome of these patients. PATIENTS AND METHODS: 64 consecutive patients (47 males and 17 females) with head injury, admitted from January 1992 to May 1994, were studied in this prospective study. Mean age was 37 +/- 18 years. Overall mortality was 23% (15/64). Student-t and Chi-square tests were used for statistical analysis, and p < 0.05 was considered statistical significant. RESULTS: Overall GCS was 7 +/- 3, survivors presenting GCS of 7.7 +/- 2.9 and non-survivors 4.7 +/- 1.5 (p = 0.04). CT were classified as follows: diffuse injury, 4 patients (7%); focal injury, 32 (53%), and mixed injury 24 (40%). Depending on the presence or absence of mesencephalic cisterns in the CT, GSC was 7.6 +/- 2.8 and 4.3 +/- 1.4, respectively (p = 0.04). Subarachnoid hemorrhage (SAH) was associated to a GCS of 6.3 +/- 2.5 and its absence to 8 +/- 3.3 (p = 0.03). The absence of mesencephalic cisterns and SAH were more frequent in the non-survivors, 72% and 32% (p = 0.01 and 0.04), respectively. ICP was recorded in 42 patients. Regarding to ICP, mortality was: 6.7% with ICP < or = 20 mmHg, 37% with ICP 21-30, 44% with ICP 31-40 and 67% with ICP > 50 mmHg (p = 0.03). Diabetes insipidus, cardiorespiratory arrest, shock, prolonged mechanical ventilation, SDRA and sepsis were the most frequent extracranial complications in non-survivors. CONCLUSIONS: There is an association between the outcome of head-injury patients with the GCS and ICP values. Absence of mesencephalic cisterns and SAH were radiologic signs of poor prognosis. Patients who died had more extracranial complications.

Adult↗
PubMed1996

[Gas exchange and hemodynamic effects of nitric oxide inhalation in patients with acute respiratory distress syndrome].

BACKGROUND: To analyze the effects on gas exchange and hemodynamics of nitric oxide inhalation in patients with acute respiratory distress syndrome. PATIENTS AND METHODS: Prospective study including 16 acute respiratory distress syndrome patients. We analyzed the acute and short-term (5 days) effects of inhaling 5 parts per million (ppm) nitric oxide on gas exchange and hemodynamics. RESULTS: After nitric oxide inhalation, PaO2/FiO2 ratio changed from 81 +/- 25 to 126 +/- 57 mmHg (p = 0.0001), mean pulmonary artery pressure decreased from 30.1 +/- 8.2 to 27.3 +/- 6.6 mmHg (p = 0.002), intrapulmonary shunt decreased from 44.6 +/- 11% to 34.1 +/- 7.9% (p = 0.002) and cardiac index did not change. Thirteen out of 16 patients (81.2%) presented at least a 20% improvement in PaO2/FiO2 ratio. In the 10 patients treated over 5 consecutive days, we observed that those who improved (increase in PaO2/FiO2 ratio higher than 20% after inhaling 5 ppm nitric oxide) showed a lower cardiac index, a higher mean pulmonary artery pressure and a higher pulmonary vascular resistance index than those who did not: Cl 3.9 +/- 0.81 vs 4.9 +/- 0.81 l/min/m2 (p < 0.001), mean pulmonary artery pressure 32.4 +/- 7 vs 25.3 +/- 4.2 mmHg (p = 0.001), and pulmonary vascular resistance index 421 +/- 199 vs 241 +/- 106 dyn.s.cm5/m2 (p = 0.003). Mean levels of methemoglobin were 1.1 +/- 0.24% (range: 0.4-1.6%), and NO2 concentration was always lower than 100 parts per billion. CONCLUSIONS: Low doses of inhaled nitric oxide induce a selective pulmonary vasodilatation and significant improvement of oxygenation in the majority of acute respiratory distress syndrome patients, although those with a hyperkinetic hemodynamic status are less likely to improve the oxygenation. These effects are maintained for at least 5 days. We did not observe rebound effects.

Acute Disease↗
PubMed1996

Prognostic indexes and mortality in critically ill patients with acute renal failure treated with different dialytic techniques.

The objective of this study was to compare the evolution of patients with acute renal failure (ARF) treated conservatively or with different dialytic techniques in an intensive care unit (ICU). From June 1992 to November 1994, 1087 consecutive patients were admitted in our ICU. Two hundred and twenty of these presented with ARF, and were divided into three groups; group I (control group): 156 patients with ARF who did not receive substitutive techniques; group II: 21 patients under intermittent hemodialysis (IHD) or peritoneal dialysis (PD); group III: 43 patients under continuous hemodiafiltration (CHDF). The studied variables were age, etiology of renal failure, requirement of dialysis, type of dialysis, length of ICU and hospital stay, and renal function outcome. APACHE II and SAPS scores were recorded on admission and analyzed for hospital mortality. Chi-square test and the analysis of variance were used for the statistical analysis. Results are presented as mean +/- SD. A p value below 0.05 was considered statistically significant. Although etiology of ARF was multifactorial, we found a high frequency of ARF due to sepsis (56.8%), hypoperfusion (58.7%), and acute tubular necrosis (62.5%). Sepsis and heart failure were clinical conditions associated to a greater mortality. We did not find any statistical difference between the two dialyzed groups for all the studied variables, nor between the three groups regarding APACHE II and hospital stay. Significant differences were found between dialyzed and non-dialyzed patients respect to age, group I: 64.1 +/- 13.6, group II: 56.4 +/- 19.7, and group III: 56.0 +/- 14.1 (p < 0.001), creatinine peak serum levels, group I: 260 +/- 130, group II: 494 +/- 209, and group III: 441 +/- 170 mumol/L (p < 0.0001), and mortality, group I: 46.9%, group II: 66.7%, and group III: 76.2% (p < 0.002). SAPS score showed differences between the control group and the CHDF group 13.9 +/- 4.8 and 16.4 +/- 5.4 (p < 0.007), respectively. The use of dialytic techniques in critically ill ARF patients is associated with greater mortality. Prognostic indexes on admission did not correctly classify our patients with ARF. Continuous hemodiafiltration does not involve greater mortality or length of stay as compared to conventional dialysis.

Acute Kidney Injury↗
PubMed1994

[Effects of support pressure ventilation with facial mask in patients with chronic respiratory failure in acute decompensation].

BACKGROUND: In previous nonrandomized studies the efficacy of ventilation with back up pressure with face mask (BUPM) in the treatment of patients with chronic obstructive pulmonary disease (COPD) in acute decompensation has been demonstrated. This study analyzes the acute effects and the clinical efficacy of BUPM in a group of patients with COPD in acute respiratory failure comparing the same with conventional therapy (CONV). METHODS: A prospective randomized study including patients with COPD in acute decompensation was carried out comparing treatment with BUPM (n = 9) with CONV treatment (n = 9). Back up pressure was fixed at 20 cmH2O. Acute gasometric effects were analyzed as well as the need for intratracheal intubation, mortality and hospital stay. RESULTS: No clinical or gasometric differences were found between either group of patients upon admission. Only the patients of the BUPM group presented a significant improvement from gaseous exchange and respiratory frequency from the first hour of treatment. Three of the nine patients (33%) of the BUPM group and nine of the CONV group of patients (100%) required intubation and mechanical ventilation (p = 0.001). CONCLUSIONS: Back up pressure face mask is the technique of choice in patients with chronic obstructive pulmonary disease in acute decompensation given that this technique leads to a rapid and significant improvement of gaseous exchange and avoids the need for intubation and mechanical ventilation in most of these patients.

Acute Disease↗
PubMed1994

Risk factors for infection by Pseudomonas aeruginosa in patients with ventilator-associated pneumonia.

OBJECTIVE: to investigate the epidemiology of infection by Pseudomonas aeruginosa in patients with ventilator-associated pneumonia (VAP). DESIGN: prospective clinical study. SETTING: a medical-surgical ICU in a university hospital. PATIENTS: we followed-up 568 mechanically ventilated patients and 83 episodes of VAP with etiologic diagnosis in 72 patients were retained for analysis. RESULTS: Ps. aeruginosa was isolated in 22 (26.5%) episodes in 18 patients. Of these episodes 7 were directly responsible for death. Using logistic regression analysis, the risk of VAP due to Ps. aeruginosa was increased in patients with chronic obstructive pulmonary disease (relative risk (RR) = 29.9, 95% confidence interval (CI) = 4.86-184.53), a mechanical ventilation period longer than 8 days (RR = 8.1, 95% CI = 1.01-65.40) and prior use of antibiotics (RR = 5.5, 95% CI = 0.88-35.01). CONCLUSIONS: patients with VAP and these factors have a greater risk of infection by Ps. aeruginosa and empirical therapy for these episodes should include anti-pseudomonal activity until etiologic diagnosis is established.

Adult↗
PubMed1994

Nosocomial bacteremia in a medical-surgical intensive care unit: epidemiologic characteristics and factors influencing mortality in 111 episodes.

OBJECTIVE: To analyze the epidemiology and factors influencing mortality of ICU-acquired bacteremia. DESIGN: Prospective clinical study. SETTING: A medical-surgical ICU in an university hospital. PATIENTS: We recorded variables from 111 consecutive ICU-acquired episodes for a 3-year period. RESULTS: The attack rate was 1.9 episodes per 100 patient-days. The commonest isolates were coagulase-negative staphylococci, Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli. Intravascular catheters were the most frequent source of infection. Overall mortality was 31.5%, and 65.7% of all deaths were directly attributable to infection. Bacteremia from intra-abdominal, lower respiratory tract or unknown origin were associated with a poor prognosis. A logistic regression analysis defined intraabdominal origin (p = 0.01, OR = 15.7) and presence of shock (p = 0.04, OR = 3.3) as independently influencing the risk of death. No significant differences were found for the remaining variables studied. CONCLUSIONS: Epidemiology and etiology of ICU-acquired bacteremia does not differ seriously in respect to nosocomial bacteremia among unselected populations, although it is associated with a greater incidence and overall mortality. Presence of shock is the most important modificable variable affecting the outcome.

Bacteremia↗
PubMed1994

Volume-controlled ventilation and pressure-controlled inverse ratio ventilation: a comparison of their effects in ARDS patients.

Volume-controlled ventilation with positive end-expiratory pressure (PEEP) (CPPV) is the conventional ventilatory approach in adult respiratory distress syndrome (ARDS) patients, but some reports suggest that pressure-controlled ventilation with an inverse inspiratory to expiratory ratio (PCIRV) may improve gas exchange in these patients. We analysed the acute effects on gas exchange, lung mechanics and haemodynamics induced by CPPV and PCIRV in ARDS patients. CPPV and PCIRV were applied randomly in ARDS patients. During CPPV, external PEEP was titrated according to the initial inflection point in the static pressure-volume (P-V) curve of the respiratory system, or it was 10 cmH2O when there was no inflection. During PCIRV, external PEEP was not applied, and inspiratory to expiratory (I/E) ratio was inversed until total PEEP was equal to the inflection point in the P-V curve, or it was 10 cmH2O. Respiratory rate, fractional inspiratory oxygen (FIO2), and tidal volume (VT) were kept constant in both modes. Eight ARDS patients were studied prospectively and admitted to a general Intensive Care Unit (ICU) of a University Hospital. Haemodynamic measurements, airflow (V), airway pressure (Paw) and VT were obtained using standard methods. We did not observe any significant change between CPPV and PCIRV with respect to: arterial oxygen tension (PaO2) 117 +/- 12 vs 107 +/- 15 mmHg (16 +/- 2 vs 14 +/- 2 kPa), arterial carbon dioxide tension (PaCO2) 40 +/- 2 vs 39 +/- 2 mmHg (6 +/- 0.3 vs 5 +/- 0.3 kPa), intrapulmonary shunt function (QS/QT) 36 +/- 3 vs 38 +/- 4%, cardiac output (CO) 7.1 +/- 0.7 vs 7 +/- 0.8 l.min-1, and total PEEP 9.7 +/- 0.6 vs 9 +/- 0.3 cmH2O. Oxygen transport and total respiratory system compliance remained unchanged in both modes. Mean Paw was slightly lower during CPPV (17 +/- 1 cmH2O) than during PCIRV (19 +/- 1 cmH2O). PCIRV does not appear to have clinical advantages over CPPV in terms of gas exchange, haemodynamics, or static lung mechanics when using the same total PEEP and minute ventilation.

Adult↗
PubMed1993

Polymicrobial bacteremia in critically ill patients.

OBJECTIVE: To characterize the epidemiology of polymicrobial bacteremia (PMB) among critically ill patients. DESIGN: Prospective clinical study. SETTING: University medical center. PATIENTS: All patients with positive blood cultures in a medical-surgical ICU. MEASUREMENTS: PMB represents 8.4% of all true bacteremia in our ICU. Most of these patients were postoperative but none had malignancies or significant immunodepression. Over three-quarters of the episodes were nosocomial. No significant differences in factors associated with PMB were found when they were compared with a cohort of 154 monomicrobial episodes. Enterobacteriaceae were the most common organisms. Intravascular devices (42.8%) were the most common source of PMB, followed by intra-abdominal origin (21.4%). The overall mortality was 7.1%, a lower rate than has previously been described. CONCLUSIONS: We suggest catheter replacement in patients who develop PMB and improving techniques of catheter maintenance in order to reduce its incidence.

Adult↗
PubMed1993

Infection of pulmonary artery catheters. Epidemiologic characteristics and multivariate analysis of risk factors.

Sixty-nine consecutive pulmonary artery catheters (PACs) were prospectively studied in a medical-surgical intensive care unit. Fifteen (21.7 percent) and two (2.9 percent) of the PACs were associated with colonization and bacteremia, respectively. These data represent an incidence of 4.98 and 0.66 episodes per 100 catheterization-days, respectively. Coagulase-negative staphylococci were the most common isolates. The source of the colonizing microorganism was the skin in 56 percent of cases, hubs in 28 percent, and unknown in 16 percent. From multivariate analysis, only more than 5 days of catheterization was significantly associated with a greater risk of colonization. Antimicrobial use was associated with negative cultures. The most useful method to diagnose colonization was the examination of both tip and intradermal segments. In addition, we suggest associate hub cultures when catheter-related bacteremia is suspected. These data may be useful in improving efficacy in the diagnosis and prevention of PAC-related infection.

Bacteremia↗
PubMed1993

A three-year study of severe community-acquired pneumonia with emphasis on outcome.

Fifty-eight consecutive patients with severe community-acquired pneumonia were studied prospectively during a three-year period. The group included 44 men and 14 women (mean age: 45.0 +/- 15.7 years). The cause of pneumonia was diagnosed in 35 (60.3 percent) cases, and the most common pathogens were Streptococcus pneumoniae (37.1 percent), Legionella pneumophila (22.8 percent) and Gram-negative bacilli (11.4 percent). The fact that Mycobacterium tuberculosis was present in four (11.4 percent) patients and Pneumocystis carinii in three (8.5 percent) is worthy of note. The overall death rate was 22.4 percent. More than 50 percent of deaths occurred within the first five days and were caused by septic shock, hemoptysis (tuberculosis) or hypoxia. However, hypoxia remains the main fatal complication and all late-occurring deaths (> 5 days) observed were due to this cause. These data could be important in planning strategies and protocols to improve prognosis.

Adult↗
PubMed1992

Nosocomial respiratory tract infections in multiple trauma patients. Influence of level of consciousness with implications for therapy.

A prospective study of 161 multiple trauma patients was carried out to determine the incidence, the causative agents, and the outcome of nosocomial respiratory tract infections in this highly selected population. Thirty-eight (23.6 percent) patients developed a nosocomial pneumonia (NP). In addition, there were four superinfections in three patients, representing an incidence of 26 percent (42 of 161). Incidence of NP was significantly greater among comatose patients (42.2 vs 13.3 percent, p less than 0.05). Furthermore, purulent tracheobronchitis was diagnosed in six patients. The causative agent of NP was identified in 36 (85.7 percent) episodes by means of fiberoptic bronchoscopies with protected specimen brush sampling. Staphylococcus aureus (55.8 percent) was the predominant pathogen isolated in multiple trauma patients in coma (Glasgow coma score [GCS] below 9 during a period greater than 24 h), while aerobic Gram-negative bacilli were responsible for the majority of cases in the remaining population studied. The overall mortality rate was 19.8 percent, but only five deaths were related to NP. We conclude that nosocomial respiratory tract infections are a frequent problem in multiple trauma patients, especially in those with GCS below 9, although this complication is associated with a relatively low mortality. Among patients with GCS below 9, S aureus was a frequent finding; consequently, antimicrobial therapy in this population needs to be different than that for the remaining multiple trauma patients with NP.

Bacteria↗
PubMed1992

Pneumonia due to Haemophilus influenzae among mechanically ventilated patients. Incidence, outcome, and risk factors.

Incidence and potential risk factors for pneumonia due to Haemophilus influenzae in adults treated with mechanical ventilation in a medical-surgical ICU were investigated. Diagnosis was established in 91 episodes and H influenzae was isolated in 20 of them. Mean onset of ventilator-associated pneumonia (VAP) due to H influenzae was 10.8 days after intubation. Six patients with H influenzae VAP died in the ICU. Of 13 risk factors for developing VAP due to H influenzae, an absence of prior antibiotic treatment was the only variable which had statistical significance (p < 0.001). In these mechanically ventilated patients, Haemophilus influenzae was a common causative agent for VAP, frequently associated with Gram-positive cocci. Episodes of H influenzae VAP were associated with a lower mortality compared with other etiologies. The epidemiologic and clinical findings indicate that patients without a prior antimicrobial treatment have increased susceptibility to infections of the airway by H influenzae.

Adolescent↗
PubMed1992

[Septic shock: epidemiology and prognosis].

As part of an infection control program in ICU, we studied prospectively 1500 consecutive patients admitted to a medical and surgical ICU from January 1988 to July 1990. Over this period of time, 69 patients developed septic shock, and 38 of them died (55.1%). Primary source of infection was the lower respiratory tract or intraabdominal in more than 50% of cases, and were related to a high mortality rate, however SS arising from a biliary tract infection is associated with a mortality rate below 20%. In the univariate analysis, nosocomial origin (p = 0.0001), creatinine serum level > 175 mumol/l (p = 0.005), multiple organ failure in the first 24 hours after shock started (p = 0.02), underlying cancer disease (p = 0.02) or liver cirrhosis (p = 0.03) were associated with a statistically significant higher risk for dying. No differences were found regarding age, sex, admission date, coma, recent surgery, prior cardiac arrest, diabetes, organ transplantation, corticosteroid therapy, cancer chemotherapy, absence of fever, bacteriology of the infection and appropriate antibiotic therapy. The multivariate analysis further identified that creatinine serum level > 175 mumol/l (p = 0.004), underlying cancer disease (p = 0.005), liver cirrhosis (p = 0.02) and nosocomial-acquired infection (p = 0.02) were independently associated to a higher risk for dying. These data allows the identification of factors related to a worst outcome. The high mortality rates recorded for septic shock still recommends the rapid transfer of the patient to an ICU as well as the use of aggressive therapy in all cases.

Cross Infection↗
PubMed1992

Nosocomial pneumonia in critically ill comatose patients: need for a differential therapeutic approach.

The purpose of this prospective clinical study was to determine the incidence, bacteriology and outcome of lower respiratory tract infections developed among 208 consecutive, critically ill comatose patients, hospitalized in a university hospital, medical-surgical intensive care unit, over a three year period. Nosocomial pneumonia developed in 53 (25%) patients after a mean of 8.1 days (range 3-31 days). Furthermore, there were five superinfections, raising the mean incidence to 28%. One patient developed secondary bacteraemia, and another two had septic shock. Fifteen (28%) patients from the pneumonia group died, and six of these deaths were considered to be directly related to nosocomial pneumonia. Identification of the causative agent, using the protected specimen brush technique, was possible in 42 episodes; in 10 (24%) of these cases more than one microorganism was isolated. Gram-positive cocci represented 53% of isolates, and Staphylococcus aureus accounted for 78% of all Gram-positive cocci, being the most frequent microorganism in this population. In conclusion, nosocomial pneumonia is a common complication of critically ill comatose patients. Its characteristic aetiological spectrum in this population should affect antibiotic prescription. Consequently, we suggest including antimicrobial drugs which are active against S. aureus in the empirical regimen until aetiological diagnosis is established.

Anti-Bacterial Agents↗
PubMed1991

Changes in gentamicin pharmacokinetic profiles induced by mechanical ventilation.

The influence of controlled mechanical ventilation (CMV) on the pharmacokinetic profile of gentamicin has been examined in 23 patients after elective open heart surgery. A parallel design was adopted in two groups of patients; 13 patients requiring CMV for at least 32 h after surgery, all of whom were able to breath spontaneously (SB) after 72 h (study group), and 10 patients who required CMV for only a brief period and who showed SB at 32 h postsurgery. Haemodynamic parameters remained stable throughout the study. Apparent volume of distribution (VZ), half-life (t1/2), total clearance (CL), peak (Cmax") and trough (Cmin") plasma levels at steady-state for target levels (6-8 microgram/ml), were measured. In the study group significant differences between CMV and SB conditions were found in VZ (mean 0.36 and 0.25 l/kg). t1/2 (mean 3.63 and 2.90 h) and Cmax" (mean 4.30 and 5.53 microgram/ml) while Cmin" (mean 1.06 microgram.ml-1 and 0.92 microgram.ml-1) did not change significantly. In contrast, the pharmacokinetics in the control group showed no differences. It appears that CMV leads to an increase in gentamicin Vz which accounts for the fall in Cmax" below the therapeutic dose range (less than 5 microgram/ml) recommended for gentamicin. It seems advisable to use a large dose of gentamicin in patients receiving CMV, even before the level is assessed.

Adult↗