The Paracetamol Absorption Test (PAT): an obligatory addition to the enteral nutrition algorithm?

Enteral nutrition (EN) is beneficial for critically ill patients. The simplest and most convenient way of providing EN is via a nasogastric (NG) tube. Feeding is often stopped because of increased volumes of NG aspirate, thought to reflect inadequate intestinal function. However, this has been shown to be an unreliable indicator of gastric function. We assessed whether the PAT (absorption of paracetamol in the small intestine depends on the rate of gastric emptying) could provide more reliable information in patients with a large NG rest.

Methods

We studied 14 consecutive patients receiving continuous EN via NG tubes who had large gastric residues (>120 ml or 2 × the hourly rate) on routine aspiration. EN was stopped and gastric emptying using the PAT was assessed immediately thereafter. The test was considered normal if the area under the concentration curve from 0–60 min (AUC₆₀) after giving 1 g of paracetamol through the NG tube was >600 mg/min/l. Results of the test were obtained within 4 h and EN was resumed in those patients with a normal result.

Results

See Table; expressed as median ± SD. EN was successfully restarted in all group 2 patients.

Conclusions

This study showed that 6/14 patients (43%) with an abnormal NG aspirate had a normal PAT; these patients continued to receive EN without untoward effects. We suggest that the PAT be performed in all patients receiving EN with a large NG aspirate; if the test was normal, EN should be continued; if the test is abnormal, use of prokinetic agents should be considered.

Table 1