How Much Blood Could a JP Suck If a JP Could Suck Blood?

OBJECTIVE: Active surgical drains minimize fluid accumulation in the postoperative period. The Jackson-Pratt (JP) system consists of a silicone drain connected by flexible tubing to a bulb. When air in the bulb is evacuated, negative pressure is applied at the surgical site to aspirate fluid. The objective of this study was to determine if the evacuation method and volume of accumulated fluid affect the pressure generated by the bulb. METHODS: Bulbs were connected to a digital manometer under various experimental conditions. A random number generator determined the initial evacuation method for each bulb, either side-in or bottom-up. Subsequent evacuations were alternated until data was collected in triplicate for each method. Predetermined amounts of water were placed into the bulb; air was evacuated; and pressure was recorded. The digital manometer was allowed to equilibrate for 1 minute prior to data acquisition. RESULTS: The average amount of pressure after a side-in evacuation of a JP bulb was 87.4 cm H2 O compared to 17.7 cm H2 O for a bottom-up evacuation (P < 0.0001). When the drain contained 25 mL, 50 mL, 75 mL, and 100 mL of fluid, the pressure applied dropped to 72.6, 41.3, 37.0, and 35.6 cm H2 O, respectively. CONCLUSIONS: JP drains generate negative pressure in order to reduce fluid accumulation at surgical sites. Although its function is frequently taken for granted, this study demonstrates that both the specific method for evacuating the bulb as well as the amount of fluid in the bulb significantly affect the performance of this device. LEVEL OF EVIDENCE: NA Laryngoscope, 129:1806-1809, 2019.

Transpalatal greater palatine canal injection: Radioanatomic analysis of where to bend the needle for pediatric sinus surgery.

BACKGROUND: The greater palatine canal (GPC) local injection is used to limit posterior bleeding during sinus surgery in adults. Given the potential for causing iatrogenic damage to the intraorbital contents, this procedure is not commonly used in the pediatric population. No studies have described the anatomic development of the GPC during facial growth. By using age-stratified radioanatomic analysis, the dimensions of the GPC and the clinical implications are described for pediatric patients. An age-stratified radioanatomic study was performed. METHODS: High-resolution computed tomography measurements included the thickness of the mucosal plane overlying the GPC, the length of the GPC, and the distance between the base of the pterygopalatine fossa (PPF) and the orbital floor. Mean distance and standard deviation were calculated for each age cohort and compared using the one-way ANOVA test. RESULTS: The GPC length correlated directly with patient age. It varied from 9.14 ± 0.11 mm in the youngest age group (<2 years) to 19.36 ± 2.76 mm in adults (18-64 years). The height of the orbit relative to the hard palate approximated the adult dimensions described in the literature by 12-13 years (49.58 ± 1.72 mm). CONCLUSION: These radioanatomic results suggest that the GPC injection described for adult patients may be safely administered to selected pediatric patients. For patients >12 years old, we recommend bending the needle 45° and inserting it 25 mm. For patients 6-12 years old, the needle should be inserted 20 mm to enter into the PPF. In patients <6 years old, the needle may safely be placed 12 mm into the GPC. Each of these descriptions is based on the minimal distance required to effectively access the PPF but with maximal safety in regard to the orbit. Further clinical correlation of these findings is necessary through future investigation.

High-resolution computed tomography analysis of the greater palatine canal.

BACKGROUND: The greater palatine foramen injection is effective for minimizing bleeding during sinus surgery. The correct depth is important to minimize risk of orbital penetration. This study analyzed the length of the greater palatine canal using high-resolution computed tomography (HRCT). METHODS: HRCT sinus scans from 100 adults were analyzed. One thousand two hundred measurements were performed by three observers. RESULTS: The mean distance of the greater palatine foramen to the orbital floor was 40+/-3 mm in men and 37+/-3 mm in women (range, 32-46 mm). The mean distance of the greater palatine foramen to the sphenopalatine foramen was 28+/-2 mm in men and 27+/-2 mm in women (range, 23-33 mm). CONCLUSION: The greater palatine foramen injection is an appropriate method to minimize bleeding during endoscopic sinus surgery. The authors recommend an injection depth of 25 mm in adults to minimize the risk of intraorbital complications.