Measuring Intrabladder Pressure With the Head of the Bed Elevated 30º: Evidence to Support a Change in Practice

Abstract

Background A 30° head-of-bed elevation is recommended for most critically ill patients. Measuring intrabladder pressure with the patient in this position is controversial. Objective To assess the feasibility of measuring intrabladder pressure with a 30° head-of-bed elevation. Methods A prospective, randomized, and experimental study. Patients had intrabladder pressure measured first while positioned supine with a 30° head-of-bed elevation and 25 mL of saline instilled into the bladder and again after the patients were randomly repositioned to supine without any head-of-bed elevation (flat) or with a 30° head-of-bed elevation while supine or in right lateral or left lateral position with either 25, 50, or 200 mL of saline instilled into the patient's bladder. Results Intrabladder pressures measured with the patient in all 3 head-of-bed elevated positions were higher than pressures measured with patients supine and flat after instillation of 25 mL of saline into the bladder, but intrabladder pressure did not differ between the 30° head-of-bed elevated positions and the supine and flat positions when 50 or 200 mL of saline was instilled into the bladder. Two-way analysis of variance showed a significant interaction between volume of saline instilled (P = .05), patient's position (P = .007), and bladder instill volume and position interaction (P = .004). Conclusion It is feasible to measure intrabladder pressure with a 30° head-of-bed elevation, and that position could be an alternative to supine positioning of patients for measurement of intrabladder pressure.

S2e guideline: positioning and early mobilisation in prophylaxis or therapy of pulmonary disorders

“…Multiple studies [ 189 , 247 , 262 , 296 ] described an increase of intra-abdominal pressure (diverted through the bladder) within the scope of an increasing elevated upper body position in cohort studies on intensive care patients (37–120 patients), wherein no critical values (> 15 mm Hg) were achieved at the 45° position (evidence level 3). No patients with an existing abdominal disorder or verifiable intra-abdominal pressure increase were found in these groups.…”

Il posizionamento della testa del paziente in terapia intensiva. Una survey tra gli infermieri italiani

“…Consequently, the problem regarding measurements of this value and future research would have to focus on the development and validation of forecasted equations to correct the IAP supine position towards a more semi-lying position. 11, 12 The IAP may change greatly according to the position of the patient. However, studies on IAP measurements should evidence the position during measurements 13 to allow the correct interpretation of the values.…”

“…Il problema di conseguenza riguarda la misurazione di questo valore e la ricerca futura dovrebbe essere incentrata sullo sviluppo e la convalida di equazioni predittive per correggere la posizione supina IAP verso la posizione semi-sdraiata. 11, 12 La IAP può modificarsi in modo significativo in base alla posizione del paziente, pertanto gli studi che trattano la misurazione IAP dovrebbero riportare la posizione durante la rilevazione 13 per interpretare correttamente i valori. Allo stesso modo l'incidenza delle lesioni da pressione risente della posizione del paziente; il loro sviluppo dipende da numerosi fattori ma alzare la testa sopra i 30°aumenta notevolmente la compressione sulla zona sacrale; da uno studio su soggetti sani volontari si è visto un importante aumento di questa e ciò potrebbe contribuire su soggetti malati allo sviluppo di ulcere da pressione.…”