Recombinant human growth hormone for reconditioning of respiratory muscle after lung volume reduction surgery

Objective: To investigate the effects of recombinant human growth hormone ( rHGH) as a "rescue treatment" in an end-stage chronic obstructive pulmonary disease patient after prolonged weaning failure. Design: Descriptive case report. Setting. Fifteen-bed intensive care unit in a university hospital. Patient. A 62-year-old man with end-stage chronic obstructive pulmonary dis ease and pulmonary emphysema after lung reduction surgery and prolonged wea ning failure after long-term mechanical ventilation. Interventions: After 42 days of unsuccessful weaning from the respirator, r HGH (27 IU/day, 0.3 IU/kg body weight/day) was administered for 20 days thr ough a subcutaneous injection in addition to standard intensive care. Measurements and Main Results. In addition to daily routine laboratory stud ies, the visceral proteins prealbumin, retinol-binding protein, and transfe rrin, and nitrogen balance were measured twice a week, as were the thyroid hormones triiodothyronine, thyroxine, and thyroid-stimulating hormone, plas ma insulin levels, and the insulin-like growth factor (IGF)-1 binding prote ins IGF-BP1 and IGF-BP3. IGF-1 was measured from day 1 to day 4 of rHGH adm inistration. Nutritional support was guided by indirect calorimetry. Additi onally, weaning variables such as peak expiratory flow rate and expiratory tidal volume were measured noninvasively. T-piece weaning trials were carri ed out daily until respiratory muscle fatigue occurred. IGF-1 increased in response to rHGH stimulation, from 103 to 230 mu g/mL, w ithin 4 days. The carrier protein IGF-BP3 increased from 126 to 283 mg/L at the end of the study period, and the inhibiting IGF-BP1 decreased initiall y from 19 to 14 mg/L and then increased until the end of the study to 31 mg /L. Nitrogen balance increased initially from 4.6 to 13.6 g/24 hrs and ther eafter decreased until the end of rHGH treatment to 8.3 g/24 hrs. Resting e nergy expenditure increased from 1800 to 2300 kcal/24 hrs. Peak expiratory flow rate increased from 0.69 to 0.88 L/sec. The expiratory tidal volume sh owed a slight increase during the study period during the daily decrease of pressure support on the ventilator setting. Respiratory muscular strength increased beginning 10 days after rHGH therapy was started. From this point , T-piece weaning trials could be prolonged almost daily. The patient was e xtubated successfully on postoperative day 75. Conclusions: This case report shows that after a prolonged catabolic state and long-term mechanical ventilation, administration of rHGH not only enhan ces the response of protein metabolism but improves respiratory muscular st rength. Therefore, it may reduce the duration of mechanical ventilation in selected patients.