Isoflurane for Life-Threatening Bronchospasm: A 15-Year Single-Center Experience

Abstract

Introduction Children with severe bronchospasm requiring mechanical ventilation may become refractory to conventional therapy. In these critically ill patients, isoflurane is an inhaled anesthetic agent available in some centers to treat bronchospasm. We hypothesized that isoflurane is safe and would lead to improved gas exchange in children with life-threatening bronchospasm refractory to conventional therapy. Methods A retrospective review was conducted and included mechanically ventilated children treated with isoflurane in a quaternary pediatric intensive care unit for life-threatening bronchospasm from 1993–2007. Demographic, blood gas, ventilator and outcome data were collected. Results Thirty-one patients with a mean age of 9.5 years (range; 0.4 – 23 years) were treated with isoflurane from 1993–2007. Mean time to initiation of isoflurane after intubation was 13 hours (0–120 hours) and the mean maximum isoflurane dose was 1.1 % (0.3 – 2.5%). Mean duration of isoflurane administration was 54.5 hours (1 – 181), with a total mean duration of mechanical ventilation of 252 hours (33.3 – 1454.5). Isoflurane led to significant improvement in pH and pCO2 within four hours of initiation (p ≤ 0.001). Complications during isoflurane administration included hypotension requiring vasoactive infusions in 24 (77%), arrhythmia in 3 (10%), neurologic side effects in 3 (10%), and pneumothorax in 1 (3%) patient. Conclusions Isoflurane led to improvement in pH and pCO2 within four hours in this series of mechanically ventilated patients with life-threatening bronchospasm. The majority of patients in this series developed hypotension, but there was a low incidence of other side effects related to isoflurane administration. Isoflurane appears to be an effective therapy in patients with life-threatening bronchospasm refractory to conventional therapy. However, further investigation is warranted given the uncertain overall impact of isoflurane in this context.

A pediatric case of life-threatening asthma managed with sevoflurane, intrapulmonary percussive ventilation and prone positioning

“…It is suggested that inhalational anesthetics can cause h y p o t e n s i o n a n d n e u r o c o g n i t ive i m p a i r m e n t . Hypotension can result through vasodilatory effects of inhalational anesthetics 3) . However, the hypotension observed on ICU admission was mitigated with sevo urane therapy in our patient, presumably because the vasodilation was resolved by the improved venous return associated with mitigation of auto-PEEP and dynamic hyperin ation 14) .…”

Adjunct Therapies for Refractory Status Asthmaticus in Children

“…Retrospective reviews demonstrate that the initiation of these gases is consistently associated with a decrease in P aCO 2 around 20 mm Hg and concomitant rise in pH of about 0.1 within a few hours of administration. 105,108,111,[113][114][115] The largest case series to date includes 31 children over a 15-y period, in which children received isoflurane for a mean duration of 55 h (range 1-181 h) and were invasively ventilated for a mean of 252 h (range 16 -1,444 h). The majority (77%) of these children developed hypotension requiring vasopressor support, but all survived without long-term sequelae.…”

Tratamento atual de crianças com asma crítica e quase fatal

“…Inhalational agents such as isoflurane and sevoflurane are potent bronchodilators that have been used in children with near-fatal asthma. ( 92 , 93 ) Their use is limited by technical issues and safety concerns. Most ventilators used in the ICU do not have a scavenger system for proper disposal of inhaled anesthetics, and anesthesia machines commonly used in the operating room may not be sufficiently sophisticated to ventilate children with near-fatal asthma.…”

“…Side effects include hypotension, arrhythmias, and movement disorders. ( 92 , 93 ) Inhaled anesthesia was reported in 3% of cases in the CPCCRN study, while ECLS was used in only 1%. ( 10 ) As of 2015, there were 256 reported cases of ECLS for near-fatal asthma (adults and children).…”