David B A Silk1, David G Quinn2. 1. Department of Academic Surgery, Imperial College London, United Kingdom prof.dba.silk@btinternet.com. 2. Research & Development, Radius International LP, Grayslake, Illinois.
Abstract
BACKGROUND: The importance of early postoperative nutrition in surgical patients and early institution of enteral nutrition in intensive care unit (ICU) patients have recently been highlighted. Unfortunately, institution of enteral feeding in both groups of patients often has to be postponed due to delayed gastric emptying and the need for gastric decompression. The design of current polyvinylchloride (PVC) gastric decompression tubes (Salem Sump [Covidien, Mansfield, MA] in the United States; Ryles [Penine Health Care Ltd, Derby, UK] in the United Kingdom and Europe) make them unsuitable for their subsequent use as either nasogastric enteral feeding tubes or for continued gastric decompression during postpyloric enteral feeding. To overcome these problems, we have designed a range of polyurethane (PU) dual-purpose gastric decompression and enteral feeding tubes that include 2 nasogastric tubes (double lumen to replace Salem Sump; single lumen to replace Ryles). Two novel multilumen nasogastrojejunal tubes (triple lumen for the United States; double lumen for the United Kingdom and Europe) complete the range. By using PU, a given internal diameter (ID) and flow area can be incorporated into a lower outside diameter (OD) compared with that achieved with PVC. The ID and lumen and flow area of an 18Fr (OD 6.7 mm) PVC Salem Sump can be incorporated into a 14Fr (OD 4.7 mm) PU tube. The design of aspiration/infusion ports of current PVC and PU tubes invites occlusion by gastrointestinal mucosa and clogging by mucus and enteral feed. To overcome this, we have designed long, single, widened, smooth, and curved edge ports with no "dead space" to trap mucus or curdled diet. Involving up to 214° of the circumference, these ports have up to 11 times the flow areas of the aspiration ports of current PVC tubes. CONCLUSION: The proposed designs will lead to the development of dual-purpose nasogastric and nasojejunal tubes that will significantly improve the clinical and nutrition care of postoperative and ICU patients.
BACKGROUND: The importance of early postoperative nutrition in surgical patients and early institution of enteral nutrition in intensive care unit (ICU) patients have recently been highlighted. Unfortunately, institution of enteral feeding in both groups of patients often has to be postponed due to delayed gastric emptying and the need for gastric decompression. The design of current polyvinylchloride (PVC) gastric decompression tubes (Salem Sump [Covidien, Mansfield, MA] in the United States; Ryles [Penine Health Care Ltd, Derby, UK] in the United Kingdom and Europe) make them unsuitable for their subsequent use as either nasogastric enteral feeding tubes or for continued gastric decompression during postpyloric enteral feeding. To overcome these problems, we have designed a range of polyurethane (PU) dual-purpose gastric decompression and enteral feeding tubes that include 2 nasogastric tubes (double lumen to replace Salem Sump; single lumen to replace Ryles). Two novel multilumen nasogastrojejunal tubes (triple lumen for the United States; double lumen for the United Kingdom and Europe) complete the range. By using PU, a given internal diameter (ID) and flow area can be incorporated into a lower outside diameter (OD) compared with that achieved with PVC. The ID and lumen and flow area of an 18Fr (OD 6.7 mm) PVC Salem Sump can be incorporated into a 14Fr (OD 4.7 mm) PU tube. The design of aspiration/infusion ports of current PVC and PU tubes invites occlusion by gastrointestinal mucosa and clogging by mucus and enteral feed. To overcome this, we have designed long, single, widened, smooth, and curved edge ports with no "dead space" to trap mucus or curdled diet. Involving up to 214° of the circumference, these ports have up to 11 times the flow areas of the aspiration ports of current PVC tubes. CONCLUSION: The proposed designs will lead to the development of dual-purpose nasogastric and nasojejunal tubes that will significantly improve the clinical and nutrition care of postoperative and ICU patients.