Isolated rib fractures in healthy young patients is most of the time no big deal. In other, more vulnerable, patients they can be lethal or significantly contribute to morbidity. A study in J Trauma dec 2011 suggests continuous intercostal nerve blockade is ready for primetime.
Rib fractures as such are unproblematic most of the time. The sometimes immense pain can however, have secondary deleterious effects.
Take for example an elderly patient with COPD. The immense rib pain could result in poor inspiratory effort, pushing the already marginally breathing patient into terminal respiratory failure.
Another example could be the polytraumatized ICU patient with rib fractures. The pain is in some cases so severe the patient will avoid coughing at any cost and so is predisposed to atelectasis through alveoli collapse or predisposed to pneumonias as he/she cant clear secretions.
Despite that, analgesia in rib fractures is a neglected issue that is also a bit more complicated than giving oral or intravenous analgesics. The pain can be immense and the opioids we end up giving have deleterious effects on breathing too. They also prolong weaning from ventilator support thus increasing the length of ICU stay.
Another option is using a thoracal epidural. It provides efficiency analgesia but the reviews available fail to demonstrate any reduced length of hospital or ICU stay. Perhaps it has to do with complications associated with epidural such as hypotension, undesired motor blocks etc.
The intercostal nerve block is one of the classic nerve blocks. It is fairly easy to learn and is also a reasonably safe procedure. It provides efficient analgesia in rib fractures. There is no motor block, no systemic hypotension and any hematomas would be harmless. Problem is how the patient needs to be re-injected every 4-6 hours.
The study in Resuscitation explores the efficacy of a continuous intercostal nerve block (CINB) through a tunnelled in catheter. The study enrolled 102 patients with three or more rib fractures localised in a pattern feasible for CINB. Measured parameters were pain scores, maximal inspiration and length of of stay.
How to do it
The technique is described in the article. They used an posterior insertion point 3-4 finger-breadths lateral to the processus spinosus. Using a scalpel and local anaesthetic they dissected down to rib. Then they gradually tunnelled their way in the cephalad direction with local anaesthetic using a disposable tunneller. At the approximate correct location the tunneller was replaced with a catheter. After which ropivacain was infused at a constant rate.
Results are in the diagrams below. Numeric Pain Score (NPS) was assessed 60 minutes after catheter placement and starting the infusion. It significantly improved and was reduced to a third. Sustained maximal inspiration (SMI) also significantly improved 60 minutes after starting infusion.
Finally, the length of hospital stay was about halved compared to a historic control group.
CINB could be a safe and efficient alternative to epidurals and opioids when managing painful rib fractures that risk having deleterious effects on coughing and spirometry. They technique used sounded simple enough. Ill have a look at our kit and see if we can come up with something similar.