Israel Medical Association Journal

Objectives: To minimize ventilatory limitation during training of patients with severe COPD[1] by applying bi-level positive pressure ventilation during training in order to augment training intensity (and effect).

Methods: The study group comprised 19 patients (18 males, 1 female) with a mean age of 64 ± 9 years. Mean forced expiratory volume in 1 second was 32 ± 4% of predicted, and all were ventilatory-limited (exercise breathing reserve 3 ± 9 L/min, normal >15 L/min). The patients were randomized: 9 were assigned to training with BiPAP[2] and 10 to standard training. All were trained on a treadmill for 2 months, twice a week, 45 minutes each time, at maximal tolerated load. Incremental maximal unsupported exercise test was performed before and at the end of the training period.

Results: BiPAP resulted in an increment of 94 ± 53% in training speed during these 2 months, as compared to 41 ± 19% increment in the control group (P < 0.005). Training with BiPAP yielded an average increase in maximal oxygen uptake of 23 ± 16% (P < 0.005), anaerobic threshold of 11 ± 12% (P < 0.05) and peak O₂ pulse of 20 ± 19% (P < 0.05), while peak exercise lactate concentration was not higher after training. Interestingly, in the BiPAP group, peak exercise ventilation was also 17 ± 20% higher after training (P < 0.05). Furthermore, contrary to our expectation, at any given work rate, ventilation (and tidal volume) in the BiPAP group was higher in the post-training test as compared to the pre-training test, and the end tidal partial pressure of CO₂ at 55 watts was lower, 40 ± 4 and 38 ± 4 mmHg respectively (P < 0.05). No improvement in exercise capacity was observed after this short training period in the control group.

Conclusion: Pressure-supported ventilation during training is feasible in patients with severe COPD and it augments the training effect. The improved exercise tolerance was associated with higher ventilatory response and therefore lower P_ETCO₂[3] at equal work rates after training.

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[1] COPD = chronic obstructive pulmonary disease

[2] BiPAP = bi-level positive pressure ventilation

[3] P_ETCO₂ = end tidal partial pressure of CO₂
 

Objective: To describe the experience of our CF[1] center in the management of CF pregnant woman from 1977 to 2004.

Methods: We analyzed 27 years of records (1977–2004) of the national CF registry of all CF women who wished to conceive and became pregnant.

Results: Eight CF women (mean age 24 ± 4.5 years) who wished to conceive had 11 pregnancies and delivered 12 neonates. The pregestational results of forced expiratory volume per 1 second varied significantly among patients (59 ± 23%), yet most (10/11) stayed stable throughout the pregnancy course. Maternal deterioration in CF condition occurred in only one mother, necessitating cesarean section. In 9 of the 11 pregnancies the women were pancreatic-insufficient. Of the 11 pregnancies, 2 CF women had diabetes mellitus and 3 developed gestational diabetes. One pregnancy occurred in a mother with a transplanted lung. Of the 12 neonates, 3 were preterm and one was born with esophageal atresia. No miscarriages, terminations or neonatal mortalities occurred. Although most of the CF mothers had FEV_1[2] below 55% before pregnancy, the maternal and neonatal outcome was favorable and lung function tests generally remained stable.

Conclusions: We conclude that pregnancy in CF is feasible with a positive maternal and neonatal outcome. Early participation of the CF physician in the wish of the CF woman to reproduce is required. The integration of an intensive multidisciplinary approach during pregnancy, which includes close follow-up of maternal and fetal condition by the various specialists, should ensure an optimal outcome.

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[1] CF = cystic fibrosis

[2] FEV₁ = forced expiratory volume per 1 sec