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Results for “Functional Residual Capacity”

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PubMed1984

Effect of postoperative intermittent positive pressure breathing on lung function.

Thirty patients undergoing elective cholecystectomy were randomly assigned to two groups. Fifteen patients received postoperative intermittent positive pressure breathing (IPPB) for four days together with physiotherapy while the other 15 had the same postoperative care but without IPPB. Vital capacity (VC), functional residual capacity (FRC) and PO2 were measured preoperatively and on days 0, 1, 3, and 5 postoperatively. The incidence of postoperative pulmonary complications utilizing chest x-ray films, sputum analysis, temperature, and clinical assessment was determined. Both groups had significant deterioration in pulmonary function but did not differ except for a greater depression in VC in the IPPB group (p less than .05). In patients receiving postoperative physiotherapy, the addition of IPPB did not usually result in improved pulmonary function.

Adult↗

PubMed1994

Diaphragmatic movement in hemiplegic patients measured by ultrasonography.

BACKGROUND: It is known that automatic breathing is controlled by centres in the lower brain stem, whereas volitional breathing is controlled by the cerebral cortical centres. In hemiplegia, lesions above the brain stem result in paralysis of limb muscles. This study was performed to determine whether the diaphragm might also be affected in patients with hemiplegia. METHODS: Studies were performed in six normal control subjects and in eight patients with complete hemiplegia caused by a lesion above the brain stem, all with no known chest disease. Full lung function tests were performed. Diaphragmatic excursion and inspired volume (VT) were measured simultaneously by M mode ultrasonography and respiratory airflow measurements. Recordings of diaphragmatic excursion were performed on each side separately during volitional and automatic breathing at a similar range of VT. RESULTS: Lung function tests lay within the normal range in all the control subjects. In the hemiplegic patients mean (SD) vital capacity was 79 (18)% and residual volume was 123(30)% of predicted. Total lung capacity and functional residual capacity were in the normal range. In the control subjects no significant difference in diaphragmatic excursion was found between volitional and automatic breathing for the same range of inspired volume. By contrast, there was a significant decrease in diaphragmatic excursion during volitional breathing compared with automatic breathing on the affected side in four of the eight hemiplegic patients. CONCLUSIONS: In four of eight hemiplegic patients reduced diaphragmatic movement was present on the paralysed side during volitional inspiration when compared with automatic inspiration. The hemidiaphragm may be involved on the affected side in patients with hemiplegia.

Aged↗

PubMed2002

Positive end-expiratory pressure and ventilation inhomogeneity in mechanically ventilated children.

OBJECTIVE: To obtain optimal titration of positive end-expiratory pressure (PEEP) during mechanical ventilation with functional residual capacity and ventilation homogeneity measurements. DESIGN: Experimental human and animal study. INTERVENTIONS: Functional residual capacity and five indices of uneven ventilation (alveolar mean dilution number, mean dilution number, lung clearance index, mixing ratio, and pulmonary clearance delay) were investigated in 22 children aged 0 to 14 yrs with lung disease and in seven rabbits by using a sulfur-hexafluoride wash-out technique. The children and rabbits were exposed to three different levels of PEEP (0, 5, and 10 cm H(2)O for the children and 0, 3 and 6 cm H(2)O for the rabbits). RESULTS: Functional residual capacity of the children increased from 256.9 +/- 178.6 mL (0 PEEP) to 280.0 +/- 201.1 mL (5 PEEP) and to 302.2 +/- 160.4 mL (10 PEEP, p <.001). Ventilation inhomogeneity decreased significantly in all children with increasing PEEP (p <.05). The alveolar mean dilution number decreased from 2.00 +/- 0.29 (0 PEEP) to 1.82 +/- 0.37 (5 PEEP) and to 1.66 +/- 0.34 (10 PEEP), and pulmonary clearance delay decreased from 74.9 +/- 24.2% to 66.6 +/- 38.1% and to 63.9 +/- 24.2%, respectively. The reduction in ventilation inhomogeneity was associated with an improvement in Pao(2) from 101 +/- 42 mm Hg (0 PEEP) to 122 +/- 48 mm Hg (5 PEEP) and to 126 +/- 53 mm Hg (10 PEEP). Functional residual capacity of the rabbits increased from 54.1 +/- 18.7 mL at 0 PEEP to 72.3 +/- 23.4 mL at 3 PEEP and to 93.9 +/- 27.3 mL at 10 PEEP. Alveolar mean dilution number decreased from 2.93 +/- 0.1 (0 PEEP) to 2.20 +/- 0.29 (3 PEEP) and to 1.45 +/- 0.13 (6 PEEP). CONCLUSIONS: In children with lung disease receiving ventilatory support, optimal PEEP titration can be obtained by the measurement of the functional residual capacity and ventilation distribution by using a sulfur-hexafluoride wash-in-wash-out technique.

Journal Article↗

PubMed1978

Influence of lung volume history on closing volume measurement during anaesthesia.

Airway closure measurements were made with the bolus technique on eight healthy subjects, who were in a supine position prior to and during anaesthesia. Measurements were made on an expiration following vital capacity (VC) and 30% VC. Closing volume (CV) was calculated prior to anaesthesia, and closing capacity (CC)--functional residual capacity (FRC) was estimated during anaesthesia. When measured from VC, CV was 703 +/- 20 ml (s.e. mean) and from 30% VC it was 440 +/- 51 ml (s.e. mean) (P less than 0.005) prior to anaesthesia. When measured from VC, CC--FRC was 370 +/- 34 ml (s.e. mean), and from 30% VC it was 343 +/- 37 (s.e. mean) (P greater than 0.05) during anaesthesia. It is concluded that volume history has little effect on CC measurement during anaesthesia and artificial ventilation, but a major influence on CC measurement in the conscious patient. Hence, it is suggested that CC, within the tidal range, is increased during anaesthesia.

Aged↗

PubMed1994

Relationship between expired lung volume, peak flow rate and peak velocity time during a voluntary cough manoeuvre.

Tussometry is a new non-invasive method of assessing laryngeal function by analysing the airflow waveform produced by a voluntary cough. Ten healthy male volunteers performed five (n = 6) or six (n = 4) voluntary cough manoeuvres at varying lung volumes from total lung capacity to functional residual capacity. During each manoeuvre, airflow (litre min-1) was plotted against time (ms) to record the peak flow generated by the cough (CPFR) and the time taken to achieve this (PVT). In addition, expired volume (CEV) was measured during each manoeuvre. Highly significant (P < 0.001) correlations existed between CPFR and PVT (r = 0.81), CPFR and CEV (r = 0.78) and PVT and CEV (r = 0.71). We conclude that PVT may vary with CPFR which in turn bears a direct relationship to expired lung volume during a cough manoeuvre. These relationships among different variables should be considered when interpreting the results of tussometry.

Adult↗

PubMedDate not supplied

[Closing volume of the respiratory airways and total lung capacity during 7-day antiorthostatic hypokinesis].

By mass spectrography and pneumotachography structural variations in total lung capacity (TLC) were investigated in 7 test subjects during 7-day head-down tilt at -15 degrees. By the 7th hour of head-down tilt TLC, vital lung capacity (VLC), functional residual capacity (FRC) and residual volume (RV) decreased significantly and closing volume (CV) increased insignificantly. The CV/FRC ratio grew from 0.82 +/- 0.03 to 1.24 +/- 0.08 (P less than 0.01), indicating the closure of respiratory pathways in certain lung structures within the tidal volume. These changes in the TLC structure persisted till day 7 but the CV/FRC ratio fell down to 1.01 +/- 0.07. The above findings can clarify the mechanism responsible for a lower oxygenation of arterial blood in the head-down position. The expiratory closure of the airways within the tidal volume causes regional changes in alveolar ventilation and ventilation-perfusion relations and, consequently, a larger venous admixture and a smaller oxygen saturation of arterial blood.

Adult↗

PubMed1983

Topographical distribution of regional lung volume in anesthetized dogs.

The distribution of regional lung volume during static deflation from total lung capacity to functional residual capacity was determined from the positions of intraparenchymal metallic markers ascertained by a biplane video roentgenographic technique in supine and prone anesthetized dogs. Regional lung volumes were linearly related to overall lung volume so that regional volume could be characterized by a ventilation index (VI), which is the ventilation per alveolus relative to the ventilation of the overall lung. For the supine position, there were vertical and cephalocaudal gradients in VI in both the upper and lower lobes. Mean VI was greater in the lower lobe than in the upper lobe, but VI was less than would be predicted from extrapolation of the upper lobe relationship. For the prone position, there was no consistent gradient in VI in any direction. The magnitude of the gradients in VI and the effects of body position suggest that, in the recumbent dog, the thoracic cavity shape is a more important determinant of regional lung volume than is the effect of gravity on the lung itself.

Anesthesia, General↗

PubMed1995

In vivo assessment of diaphragm contraction by ultrasound in normal subjects.

BACKGROUND: Ultrasound allows observation of the thickness of the diaphragm in the zone of apposition in vivo during relaxation and maximum inspiratory efforts. METHODS: Changes of diaphragm thickness were studied by B mode (two dimensional) ultrasound in 13 healthy men aged 29-54 years in the seated position. A high resolution 7.5 MHz ultrasound transducer was held perpendicular to the chest wall in the line of a right intercostal space between the anteroaxillary and mid-axillary lines to observe the diaphragm in the zone of apposition 0.5-2 cm below the costophrenic angle. The changes of thickness were observed while breath holding at total lung capacity (TLC), functional residual capacity (FRC), and residual volume (RV). At FRC the thickness while relaxing against a closed mouthpiece and during a maximum inspiratory mouth pressure (PImax) manoeuvre was recorded. The thickening ratio (TR) was calculated as TR = thickness during PImax manoeuvre/thickness while relaxing. RESULTS: Mean (SD) thickness was 4.5 (0.9) mm at TLC, 1.7 (0.2) mm at FRC, and 1.6 (0.2) mm at RV. During the PImax manoeuvre at FRC mean thickness increased from 1.7 (0.2) mm during relaxation to 4.4 (1.4) mm, while mean PImax and TR were -104 (33) cm H2O and 2.6 (0.7), respectively. There was a high degree of correlation between TR and the pressure achieved during the maximum inspiratory manoeuvre (r = -0.82). CONCLUSIONS: Ultrasound provides a non-invasive assessment of diaphragm thickness with change of lung volume and during the PImax manoeuvre which should prove useful in assessing diaphragm mass and contraction in respiratory and muscle disease.

Adult↗

PubMed1990

Effects of body position and lung volume on in situ operating length of canine diaphragm.

The performance of the diaphragm is influenced by its in situ length relative to its optimal force-generating length (Lo). Lead markers were sutured to the abdominal surface of the diaphragm along bundles of the left ventral, middle, and dorsal regions of the costal diaphragm and the left crural diaphragm of six beagle dogs. After 2-3 wk postoperative recovery, the dogs were anesthetized, paralyzed, and scanned prone and supine in the Dynamic Spatial Reconstructor (DSR) at a total lung capacity (TLC), functional residual capacity (FRC), and residual volume (RV). The location of each marker was digitized from the reconstructed DSR images, and in situ lengths were determined. After an overdose of anesthetic had been administered to the dogs, each marked diaphragm bundle was removed, mounted in a 37 degrees C in vitro chamber, and adjusted to Lo (maximum tetanic force). The operating length of the diaphragm, or in situ length expressed as percent Lo, varied from region to region at the lung volumes studied; variability was least at RV and increased with increasing lung volume. At FRC, all regions of the diaphragm was shorter in the prone posture compared with the supine, but there was no clear gravity-dependent vertical gradient of in situ length in either posture. Because in vitro length-tension characteristics were similar for all diaphragm regions, regional in vivo length differences indicate that the diaphragm's potential to generate maximal force is nonuniform.

Animals↗

PubMed2000

Estimation of diaphragm length in patients with severe chronic obstructive pulmonary disease.

In patients with advanced chronic obstructive pulmonary disease (COPD) diaphragm function may be compromised because of reduced muscle fibre length. Diaphragm length (L(Di)) can be estimated from measurements of transverse diameter of the rib cage (D(Rc)) and the length of the zone of apposition (L(Zapp)) in healthy subjects, but this method has not been validated in patients with COPD. Postero-anterior chest radiographs were obtained at total lung capacity (TLC), functional residual capacity (FRC) and residual volume (RV) in nine male patients with severe COPD (mean [S.D.]; FEV(1), 23 [6] %pred.; FRC, 199 [15] %pred.). Radiographs taken at TLC were used to identify the lateral costal insertions of the diaphragm (L(Zapp) assumed to approach zero at TLC). L(Di) was measured directly and also estimated from measurements of L(Zapp) and D(Rc) using a prediction equation derived from healthy subjects. The estimation of L(Di) was highly accurate with an intraclass correlation coefficient of 0.93 and 95% CI of approximately +/-8% of the true value. L(Di) decreased from 426 (64) mm at RV to 305 (31) mm at TLC. As there were only small and variable changes in D(Rc) across the lung volume range, most of the L(Di) changes occurred in the zone of apposition. Additional studies showed that measurements of L(Di) from PA and lateral radiographs performed at different lung volumes were tightly correlated. These results suggest that non-invasive measurements of L(Zapp) in the coronal plane (e.g. using ultrasonography) and D(Rc) (e.g. using magnetometers) can be used to provide an accurate estimate of L(Di) in COPD patients.

Aged↗

PubMed1996

Lung volumes and pressure-volume relations of the respiratory system in small ventilated neonates with severe respiratory distress syndrome.

Total lung capacity (TLC), inspiratory capacity (IC), functional residual capacity (FRC), and deflation pressure-volume (P-V) curves were studied in 16 intubated neonates (540-3300 g), 10 with severe respiratory distress syndrome (RDS) and 6 air-ventilated with normal chest radiograms. FRC was measured using washout of a tracer gas (sulfur hexafluoride), and TLC and IC were calculated after inflating the lungs to 30 cm H2O. P-V curves were obtained during expiration from TLC using an interrupter technique, and the steepest slope of the curve, i.e. the maximum compliance (Crs-max), was calculated. In addition, an index of ventilation inhomogeneity (pulmonary clearance delay, PCD) was computed from the shape of the SF6 washout curve. TLC/body weight was less in the RDS group than in the air-ventilated group (median 19 and range 16-43 mL/kg versus 48 and 43-52 mL/kg, respectively; p < 0.01), mainly because of a marked reduction in IC (median 11 and range 8-24 mL/kg versus 29 and 28-40 mL/kg; p < 0.01). The flatter P-V curve in the RDS group was reflected also in a lower Crs-max (median 0.7 and range 0.4-1.7 cm H2O-1 kg-1) than in the air-ventilated group (2.3 and 2.0-3.1 mL cm H2O-1 kg-1, respectively; p < 0.01). Thus, there was no overlap in IC or Crs-max between the groups, suggesting that reductions in these measures may be main characteristics of RDS. On the other hand, no difference in PCD was found, indicating that, in infants with RDS, the tidal volume is distributed fairly homogeneously to the ventilated parts of the lungs.

Functional Residual Capacity↗

PubMed2003

Hyperoxia prevents carrageenan-induced enlargement of functional residual lung capacity in rats.

Experimental pneumonia induced by intratracheal application of carrageenan or paraquat increases the functional residual lung capacity (FRC) in rats. The mechanism of this increase is not clear, but a decrease in PO(2) may be involved. To test this possibility, we attempted to eliminate the PO(2) decrease in carrageenan-treated rats by exposing them to hyperoxia. Animals of the first group were exposed to 7 days of hyperoxia (F(I)O(2) 0.78-0.84, group Car+O(2)) after intratracheal application of carrageenan (0.5 ml of 0.7 % carrageenan in saline), whereas animals of the second group were given the same dose of carrageenan but breathed air (group Car+A). The third group of rats was kept for seven days in hyperoxia (group O(2)) and the fourth group served as controls (C). The animals were then anesthetized and intubated and their ventilatory parameters and FRC were measured during air breathing. Carrageenan application induced a FRC increase (Car+A 2.0+/-0.2 ml, C 1.6+/-0.1 ml), which was not seen in carrageenan-treated rats exposed to hyperoxia (Car+O(2) 1.6+/-0.1 ml). Hyperoxia alone did not affect the value of FRC (O(2) 1.5+/-0.1 ml). These results support the hypothesis that a decrease in PO(2) plays an important role in the carrageenan-induced increase of FRC in rats.

Animals↗

PubMed1992

Pulmonary responses to lower body negative pressure and fluid loading during head-down tilt bedrest.

Exposure to microgravity redistributes body fluids with important secondary effects on cardiovascular function. We tested the hypothesis that the fluid shifts also affect pulmonary gas exchange. Microgravity was simulated in six male volunteers by a 10-day period of bedrest at 6 degrees head-down tilt (HDT). Lower body negative pressure (LBNP) and intravenous saline loading superimposed acute changes in fluid distribution on the prolonged effects of HDT. HDT produced relative dehydration and hypovolemia with decreased pulmonary blood flow and diffusing capacity. Before bedrest, pulmonary blood flow decreased by 24% during LBNP and diffusing capacity by 7%, while functional residual capacity increased by 14% (p less than 0.05). Intravenous saline loading caused a 24% increase in pulmonary blood-flow (p less than 0.05). Functional residual capacity decreased by 10% and diffusing capacity by 6% (p less than 0.05). Lung tissue volume did not change significantly. Head-down tilt had only minor effects on the responses to LBNP and saline loading. We conclude that LBNP and intravenous saline loading produce major changes in pulmonary blood-flow and minor effects on pulmonary gas exchange, and that the response to acute changes in fluid distribution is not significantly altered during simulated microgravity.

Adult↗

PubMed1994

Randomized trial of long-term diuretic therapy for infants with oxygen-dependent bronchopulmonary dysplasia.

STUDY OBJECTIVE: To determine whether long-term oral diuretic therapy would improve the pulmonary function of preterm infants with bronchopulmonary dysplasia. DESIGN: Randomized, double-blind, placebo-controlled study. SETTING: Level III intensive care nursery. INTERVENTION: We randomly selected 43 stable patients with oxygen-dependent bronchopulmonary dysplasia to receive either orally administered spironolactone and chlorothiazide or placebo. These drugs were continued until the patients no longer required supplemental oxygen. Both groups received furosemide as needed. MEASUREMENTS AND RESULTS: Each infant had pulmonary function tests at study entry, 4 weeks after study entry, 1 week and 8 weeks after being weaned to room air and off study drugs, and at 1 year of corrected age. Pulmonary function tests include dynamic pulmonary compliance, airway resistance, thoracic gas volume, and maximal expiratory flow at functional residual capacity; most of the infants had functional residual capacity measured. Between the first and second pulmonary function tests (while the infants were receiving diuretic or placebo), the infants in the diuretic group had a significant improvement in dynamic pulmonary compliance (46%; p < 0.001) and airway resistance (31%; p < 0.05); there were no changes in compliance or resistance in the placebo group. Although patients in both the diuretic and the placebo groups required progressively less supplemental oxygen, by 4 weeks after study entry the patients in the diuretic group needed less supplemental oxygen than did those in the placebo group (p < 0.01). There were no significant differences in results of serial pulmonary function tests in either group after discontinuation of diuretic therapy. Despite the significant differences in pulmonary function between the two groups, there was no significant difference between them in the total number of days that supplemental oxygen was required. Significantly more infantsin the placebo group received more than 10 doses of furosemide on an as-needed basis. CONCLUSIONS: Long-term diuretic therapy in stable infants with oxygen-dependent bronchopulmonary dysplasia, after extubation, improves their pulmonary function and decreases their fractional inspired oxygen requirement, but does not decrease the number of days that they require supplemental oxygen. The improvement in pulmonary function associated with diuretic therapy is not maintained after treatment is discontinued.

Analysis of Variance↗

PubMed1988

The carbon dioxide rate of rise in awake apneic humans.

Currently available estimates of the PaCO2 rate of rise in resting humans with resting lung volume were gathered during general anesthesia. The PaCO2 rate of rise during apnea in awake subjects was determined to acquire a value that may be more applicable to awake, ventilator-dependent, critically ill patients. Clinically, apnea occurs at functional residual capacity. With FiO2 = 1.0, 20 volunteers held their breaths at functional residual capacity for 0, 10, and 20 seconds, and then for as long as possible. They exhaled through an infrared CO2 analyzer after each interval to determine end-tidal pCO2. An estimate of the logarithmic PaCO2 rise during breath holding at functional residual capacity was 7 mmHg during the first 10 seconds (43 mmHg/minute), 2 mmHg during the next 10 seconds (13 mmHg/minute), and 6 mmHg/minute thereafter. In conclusion, PaCO2 increases more rapidly in awake apneic humans than earlier thought. The values reported herein probably are better for estimating duration of apnea in conscious, critically ill patients than are values obtained during general anesthesia.

Adult↗

PubMed1985

Pulmonary function and ventilatory response to chemical stimuli in familial myopathy.

We studied the pulmonary function and ventilatory response to carbon dioxide and hypoxia in three sisters aged 16, 13, and 10 years who presented with droopy eyelids, external ophthalmoplegia, hearing loss, speech difficulty, and truncal muscular weakness. Pulmonary function test results showed decreased maximum static pressure, reduced vital capacity and total lung capacity, normal functional residual capacity, elevated residual volume, and reduced dynamic pulmonary volumes. The degree of functional abnormality paralleled the severity of clinical manifestations. The characteristic picture of pulmonary functional abnormality was distinct from either restrictive disorders of pulmonary origin or obstructive pulmonary diseases. The ventilatory response to hypoxia was markedly diminished and hypercapnic response was moderately diminished in all three patients.

Adolescent↗

PubMed1993

Exogenous surfactant therapy increases static lung compliance, and cannot be assessed by measurements of dynamic compliance alone.

OBJECTIVE: To study the immediate effects of exogenous surfactant therapy on blood gases, lung volumes, and lung mechanics in adult rabbits with experimentally induced respiratory distress syndrome. DESIGN: Prospective randomized, controlled study. SETTING: Laboratory and animal facility of a large university. SUBJECTS: Twelve adult New Zealand white rabbits. INTERVENTIONS: Respiratory failure was induced by repeated bilateral whole-lung lavage with saline (30 mL/kg body weight). After the last lavage, the animals were randomly assigned to two groups. Group 1 received surfactant (120 mg/kg body weight) that was suspended in a 0.6% sodium chloride solution. Group 2 received comparable volumes of the same hypotonic solution and served as controls. MEASUREMENTS AND MAIN RESULTS: Before and after endotracheal surfactant instillation, blood gases and functional residual capacity were measured, and lung mechanics from tidal volumes and pressure-volume curves were calculated. Functional residual capacity was measured by a computerized, multiple-breath, washin-washout method using sulfur hexafluoride (SF6) as tracer gas. The pressure-volume curves were obtained by an occlusion technique originally described for measuring static breath-by-breath compliance. The technique was modified for present use and fully computerized. Within 60 mins after surfactant instillation, there were marked improvements in Pao2 (61 +/- 7 torr [8.2 +/- 0.9 kPa] to 470 +/- 47 torr [62.6 +/- 6.2 kPa]) and in functional residual capacity (7.6 +/- 1.4 to 17.7 +/- 1.6 mL/kg body weight) at unchanged ventilatory settings. The pressure-volume curves became steeper over time and the pressure-volume curves for total lung volume were restored to an almost normal state. Maximum compliance calculated from the pressure-volume curves increased by 92% but there was no significant change in dynamic compliance. In the control group, no improvements in any measured or calculated lung parameters were seen. CONCLUSIONS: The findings indicate that during mechanical ventilation, the effects of surfactant therapy on lung mechanics are best characterized by changes in functional residual capacity and maximum compliance obtained from static pressure-volume curves and not by dynamic compliance.

Animals↗

PubMed1997

Assessment of lung function in neonates during extracorporeal membrane oxygenation.

We report our experience with pulmonary function testing in 11 out of 22 full-term neonates with severe respiratory failure, treated at the ECMO center Graz (Austria) during the period from 1990 to 1995. Altogether 17 out of 22 patients survived ECMO and all of them were successfully weaned from ECMO. Pulmonary function was assessed by monitoring expiratory tidal volume on the ventilator and estimating respiratory system compliance from the ratio tidal volume/(PIP-PEEP). In addition, compliance, and functional residual capacity were measured using a computerized pulmonary function system (PEDS). Compliance (mean +/- SD) decreased markedly after 24 hours of ECMO, compared with baseline values (0.20 +/- 0.12 vs 0.12 +/- 0.13 ml/cmH2O/kg) and was significantly higher (0.43 +/- 0.14 ml/cmH2O/kg, p < 0.01) before ECMO stop. When tidal volumes increased continuously ECMO blood flow could be decreased, indicating lung recovery. Most patients had a tidal volume of > 7 ml/kg prior to decannulation. Functional residual capacity and corresponding dynamic compliance, measured in 5 patients, ranged from 18.6 to 29.6 ml/kg and 0.49 to 0.57 ml/cmH2O/kg at this time. Functional residual capacity (mean +/- SD) increased significantly when surfactant was administered to promote weaning from ECMO (8.28 +/- 0.9 vs 19.0 +/- 1.0 ml/kg, p < 0.01). We conclude that the assessment of lung function has improved our understanding of pulmonary recovery during ECMO. Its clinical significance in determining the optimum time of weaning from ECMO needs further evaluation.

Extracorporeal Membrane Oxygenation↗