Clinical Diagnosis of Pneumothorax Is Late: Use of Trend Data and Decision Support Might Allow Preclinical Detection

Abstract

Pneumothorax in the newborn has a significant mortality and morbidity. Early diagnosis would be likely to improve the outlook. Forty-two consecutive cases of pneumothorax that developed after admission to a tertiary referral neonatal medical intensive care unit over 4 y from 1993 to 1996 were reviewed. The time of onset of the pneumothorax was determined by retrospective evaluation of the computerized trend of transcutaneous carbon dioxide (tcpCO 2 ) and oxygen tensions. The timing of the occurrence in the notes and x-rays determined the time of clinical diagnosis noted at the time. The difference was the time the condition was undiagnosed. The overall mortality before discharge was 45% (19cases), four patients succumbing within 2 h. The median time (range) between onset of pneumothorax and clinical diagnosis was 127 min (45-660 min). In most cases, the endotracheal tube was aspirated and the transcutaneous blood gas sensor was repositioned, and in at least 40% of the cases, the baby was reintubated before the diagnosis was made. Reference centiles were constructed for level of tcpCO 2 and slope of the trended tcpCO 2 over various time intervals (in minutes) from 729 infants from 23 to 42 wk gestation who needed intensive care during the first 7 d of life from the same time period. The 5-min tcpCO 2 trend slopes were compared in index and matched control infants. The presence of five consecutive and overlapping 5-min slopes greater than the 90th centile showed good discrimination for a pneumothorax (area under the receiver operating characteristic curve, 89%). We concluded that 1) the clinical diagnosis of pneumothorax was late, occurring when infants decompensate; 2) trend monitoring of tcpCO 2 might allow the diagnosis to be made earlier if used properly; and 3) use of reference centiles of the trended slopes of tcpCO 2 might be used for automatic decision support in the future. Abbreviations tcpCO 2 , transcutaneous carbon dioxide tension tcpO 2 , transcutaneous oxygen tension FiO 2 , fraction of inspired oxygen ROC, receiver operating characteristic AUC, area under the curve A pneumothorax is a life-threatening complication of ventilatory assistance in the neonatal unit and has a high mortality (1, 2) and morbidity (3) Pneumothoraces are generally thought to develop rapidly. They are usually diagnosed once the infant has decompensated sufficiently to make it obvious that there is a serious clinical problem. Under these circumstances, it may be only a short period before the baby is critically ill because of the development of tension within the thoracic cavity. This problem is becoming less common, but this may mean that junior medical and nursing staff caring for these infants have become less familiar with the condition. As a consequence, the diagnosis may be made even later in the clinical course and the staff may have less skill in the emergency treatment. It is probable that the earlier a pneumothorax is drained, the less damage will occur from hypoxia, hypercarbia, and venous and arterial pressure chan...

Impaired Early Neurologic Outcome in Newborn Piglets Reoxygenated with 100% Oxygen Compared with Room Air after Pneumothorax-Induced Asphyxia

“…Therefore, it is not surprising that we observed significant cerebral damage in both groups of asphyxiated animals. Moreover, pneumothorax is far more frequent in newborns than in any other period of life (23,32,33), and the brain of the newborn piglet is comparable both histologically (34) and electrophysiologically (35) with that of human infants at 36 -38 wk of gestation.…”

“…The clinical status of the animals worsened continuously, and by the end of 1 h after the induction of pneumothorax, gasping, bradyarrhythmia, arterial hypotension, hypoxemia, and severe combined acidosis had developed. The pneumothorax was then relieved, and the response to therapy was controlled by transillumination (Wild M4000 fiberscope, Heerburgg, Switzerland) of the thorax (18,22,23). Asphyxiated animals were randomly divided into two groups.…”

Sequential changes of hemodynamics and blood gases in newborn piglets with developing pneumothorax

“…Therefore, the early identification of a pneumothorax could be of great importance to optimize management and minimize neurological impairment. 18,22 Limitations There were several limitations in our study. We did not evaluate brain pathology post mortem; therefore the severity of brain injury in these piglets with experimental pneumothorax is unknown.…”

“…However detrimental cardiac and/or cerebral effects may precede the clinically significant pneumothorax. Indeed, McIntosh et al 18 reported that the clinical diagnosis of pneumothorax was late, occurring when neonates decompensated. Therefore, we designed this study to explore the temporal changes in hemodynamics and oxygenation, including surrogates of cerebral measurements (carotid arterial flow and oxygen delivery) during a progressive pneumothorax in neonatal piglets.…”

Intensive care monitoring: past, present and future

“…Figure 2a shows the pattern of cold stress 2 , seen within days of instituting our trend monitoring system. More difficult, but fairly consistent, has been the picture of the occurrence of a pneumothorax where the transcutaneous carbon dioxide level sharply increases usually at the same time as a sharp decrease in the transcutaneous oxygen 3 (Fig 2b). We believed that our system helped in management but wish to see whether there was any difference in outcome.…”