PYLORIC MOTILITY - SLEEVE SENSOR VERSUS STRAIN-GAUGE TRANSDUCER

Intraduodenal infusion of nutrients has been shown by intraluminal sle eve-sidehole manometry to suppress antral contractions and stimulate i solated pyloric pressure waves (IPPWs) in humans. It is still unresolv ed, whether these pyloric contractions occur within an otherwise quies cent zone of motor and electrical activity and whether the presence of the sleeve sensor itself affects this nutrient-associated response. I n four conscious dogs, comparisons were made between paired recordings of myoelectrical and motor activities of the antropyloroduodenal regi on with serosal strain gauge transducers and extacellular bipolar elec trodes in the presence and absence of an intraluminal manometric sleev e-sidehole assembly during intraduodenal infusions of saline and a tri glyceride emulsion (Intralipid 10%, 0.5 kcal/min). Of 287 isolated pyl oric pressure waves, detected by the manometric sleeve sensor, 75% wer e detected as isolated pyloric contractions by the strain gauge transd ucers and 72% occurred in the absence of electrical spike activity in the distal antrum or proximal duodenum The. lower incidence of isolate d pyloric contractions (strain gauges) was related to: (1) insensitivi ty of the pyloric strain gauge transducer in comparison to the manomet ric sleeve sensor (10%), and (2) inability of the manometric sleeve-si dehole assembly to detect pressure waves in the distal antrum (7%) or proximal duodenum (8%) during antral or duodenal wall motion. The pres ence of the sleeve sensor itself did not affect the number of lipid-in duced isolated pyloric contractions but increased their amplitude [med ian 9 (7-15) mN vs 4 (2-6) mN; P < 0.05]. We conclude that: (1) most i solated pyloric pressure waves recorded by the manometric sleeve senso r represent contractions truly isolated to the pylorus, and (2) the pr esence of a sleeve sensor does not influence the number of isolated py loric contractions.