Plasma pro-atrial natriuretic peptide to indicate fluid balance during cystectomy: a prospective observational study

Feasibility and safety of laparoscopic radical cystectomy for male octogenarians with muscle-invasive bladder cancer

This study was designed to evaluate the safety and feasibility of laparoscopic radical cystectomy (LRC) for male octogenarian patients with muscle-invasive bladder cancer (MIBC). Briefly, a total of 57 male octogenarian patients (A group) with bladder carcinoma were enrolled and underwent LRC and intracorporeal pelvic lymph node dissection with bilateral cutaneous ureterostomy from May 2016 to December 2022. Besides, 63 male patients (age < 80 years old) with bladder carcinoma undergoing LRC and 17 octogenarian male patients with bladder carcinoma undergoing open radical cystectomy (ORC) were enrolled in B and C groups as control. All perioperative clinical materials and outcomes of long-term follow-up, and complication were collected. The specific results were shown as follows. Compared with C group, the operation time and resected lymph node in A group was increased, and the estimated blood loss, the number of transfusion needed, duration of pelvic drainage and hospital stay after surgery was decreased. The death rate and ileus complication rate were higher in A group (12 cases) than in C group (15 cases). The cases of ureteral stricture in A group (13 cases) was decreased compared with that in C group. Overall, LRC and bilateral cutaneous ureterostomy are safe, feasible and better choices for the treatment of male octogenarian patients with MIBC. The octogenarian receiving cutaneous ureterostomy heals slowly and exists certain incomplete intestinal obstruction after surgery.

Mid‐regional plasma pro‐atrial natriuretic peptide and stroke volume responsiveness for detecting deviations in central blood volume following major abdominal surgery

Background

A reduced central blood volume is reflected by a decrease in mid‐regional plasma pro‐atrial natriuretic peptide (MR‐proANP), a stable precursor of ANP, and a volume deficit may also be assessed by the stroke volume (SV) response to head‐down tilt (HDT). We determined plasma MR‐proANP during major abdominal procedures and evaluated whether the patients were volume responsive by the end of the surgery, taking the fluid balance and the crystalloid/colloid ratio into account.

Methods

Patients undergoing pancreatic (n = 25), liver (n = 25), or gastroesophageal (n = 38) surgery were included prospectively. Plasma MR‐proANP was determined before and after surgery, and the fluid response was assessed by the SV response to 10^° HDT after the procedure. The fluid strategy was based mainly on lactated Ringer's solution for gastroesophageal procedures, while for pancreas and liver surgery, more human albumin 5% was administered.

Results

Plasma MR‐proANP decreased for patients undergoing gastroesophageal surgery (−9% [95% CI −3.2 to −15.3], p = .004) and 10 patients were fluid responsive by the end of surgery (∆SV > 10% during HDT) with an administered crystalloid/colloid ratio of 3.3 (fluid balance +1389 ± 452 ml). Furthermore, plasma MR‐proANP and fluid balance were correlated (r = .352 [95% CI 0.031–0.674], p < .001). In contrast, plasma MR‐proANP did not change significantly during pancreatic and liver surgery during which the crystalloid/colloid ratio was 1.0 (fluid balance +385 ± 478 ml) and 1.9 (fluid balance +513 ± 381 ml), respectively. For these patients, there was no correlation between plasma MR‐proANP and fluid balance, and no patient was fluid responsive.

Conclusion

Plasma MR‐proANP was reduced in fluid responsive patients by the end of surgery for the patients for whom the fluid strategy was based on more lactated Ringer's solution than human albumin 5%.

Effect of adrenaline on serum mid-regional pro-atrial natriuretic peptide and central blood volume

New Findings

What is the central question in this study?

Atrial natriuretic peptide (ANP) is secreted in response to atrial wall distension and thus allows for evaluation, albeit indirect, of the central blood volume. Adrenaline has chronotropic and inotropic effects. We evaluated whether the chronotropic and inotropic effects of adrenaline were reflected in mid‐regional proANP.

What is the main finding and its importance?

Central blood volume remained stable with infusion of adrenaline and yet mid‐regional proANP increased. Thus, the chronotropic and inotropic state of the heart or adrenaline directly induces release of ANP variants from the myocytes.

Abstract

Atrial natriuretic peptide (ANP) has vasodilatory, natriuretic and diuretic properties. It is secreted in response to atrial wall distension and thereby provides an indirect evaluation of central blood volume (CBV). Adrenaline has chronotropic and inotropic effects that increase cardiac output. In the present study, we evaluated whether these effects were influenced by an increase in CBV and reflected in mid‐regional proANP (MR‐proANP) concentrations in the circulation, a stable proxy marker of bioactive ANP. Changes in CBV were evaluated by thoracic electrical admittance and haemodynamic variables monitored by pulse‐contour analysis during two intervals with graded infusion of adrenaline. Adrenaline infusion increased heart rate (by 33 ± 18%) and stroke volume (by 6 ± 13%), hence cardiac output (by 42 ± 23%; all P < 0.05). The increase in cardiac output did not result from an increase in CBV, because thoracic electrical admittance remained stable (−3 ± 17%; P = 0.230). Serum MR‐proANP concentrations were increased (by 26 ± 25%; P < 0.001) by adrenaline infusion and remained elevated 60 min postinfusion. We conclude that MR‐proANP in the circulation is affected not only by CBV, but also by increased chronotropy/inotropy of the heart, or that adrenaline directly induces release of ANP variants from the myocytes.

The central blood volume as measured by thoracic electrical impedance and plasma proANP is not compromised by donation of 900 mL of blood in men

OBJECTIVES

To evaluate whether the donation of 900 mL of blood reduces the central blood volume (CBV) assessed by thoracic electrical impedance (TI) and plasma pro-atrial natriuretic peptide (proANP).

BACKGROUND

Donation of 450 mL of blood carries a 1% risk of a vasovagal reaction. Withdrawal of 900 mL of blood decreases cardiac output; however, the effect on CBV remains unknown.

METHODS/MATERIALS

A randomised, single-blinded, placebo-controlled, crossover design was used, where 21 healthy semi-recumbent men donated 2 × 450 mL blood or were sham-phlebotomised. Changes in CBV were estimated by proANP and TI at 1.5 (TI_1.5 ) and 100 (TI₁₀₀ ) kHz, reflecting extracellular volume and (regional) total body water, respectively, and the index value (IDX; 1/T_1.5 -1/TI₁₀₀ ) was used to estimate changes in intracellular (red cell) volume. Systolic, diastolic and mean arterial blood pressure; heart rate; stroke volume; cardiac output; and systemic vascular resistance were monitored. After completion of the study, 1000 mL of isotonic saline was infused.

RESULTS

Changes (mean% ± SD) in TI_1.5 , TI₁₀₀ and IDX were similar after 450 mL (-0.2 ± 1.6%, 0.0 ± 1.1%, -0.4 ± 10.1%) and 900 mL (0.1 ± 1.6%, 0.2 ± 1.5% and -2.0 ± 15.8%) of blood donation compared to after a sham donation of 450 mL (-0.9 ± 1.2%, -0.5 ± 1.5% and -0.1 ± 6.1%) and 900 mL (-1.2 ± 1.5%, -0.6 ± 1.3% and 0.5 ± 9.9%). In addition, changes in plasma proANP were similar after 450 and 900 mL of blood donation (-0.8 ± 6.7% and -7.6 ± 7.9%) as after sham donations (1.3 ± 7.3% and -4.5 ± 5.6%). Monitoring haemodynamic variables revealed that stroke volume decreased after the donation of 900 mL of blood (-12 ± 12 mL) compared to sham donations.

CONCLUSION

During a 900-mL blood loss in semi-recumbent men, CBV measured by TI and plasma proANP is not affected.

Effect of hypotensive hypovolemia and thoracic epidural anesthesia on plasma pro-atrial natriuretic peptide to indicate deviations in central blood volume in pigs: a blinded, randomized controlled trial

Purpose

Changes in plasma pro-atrial natriuretic peptide (proANP) may indicate deviations in the central blood volume (CBV). We evaluated the plasma proANP response to hypotensive hypovolemia under the influence of thoracic epidural anesthesia (TEA) in pigs. We hypothesized that plasma proANP would decrease in response to hypotensive hypovolemia and that TEA would aggravate the proANP response, reflecting a further decrease in CBV.

Design

Randomized, blinded, controlled trial.

Setting

A university-affiliated experimental facility.

Participants

Twenty pigs randomized to administration of saline (placebo) or bupivacaine with morphine (TEA) in the epidural space at Th8-Th10.

Interventions

Relative hypovolemia was established by an inflatable Foley catheter positioned in the inferior caval vein just below the heart (caval obstruction), and hemorrhage-induced hypovolemia was by withdrawal of blood from the femoral artery, both aiming at a mean arterial pressure (MAP) of 50–60 mmHg. Hemodynamic variables and plasma proANP were determined before and after the interventions.

Results

Caval obstruction and withdrawal of blood reduced MAP to 50–60 mmHg. Accordingly, cardiac output, central venous pressure, and mixed venous oxygen saturation decreased (p<0.05). Yet, plasma proANP was stable after both caval obstruction (TEA: 72 [63–78] to 80 pmol/L [72–85], p=0.09 and placebo: 64 [58–76] to 69 pmol/L [57–81], p=0.06) and withdrawal of blood (TEA: 74 [73–83] to 79 pmol/L [77–87], p=0.07 and placebo: 64 [56–77] to 67 pmol/L [58–78], p=0.15).

Conclusion

Plasma proANP was stable in response to relative and hemorrhage-induced hypovolemia to a MAP of 50–60 mmHg, and the response was independent of TEA. The findings suggest that alterations in plasma proANP do not follow deviations in CBV during hypotensive hypovolemia in pigs.

Effect of early versus delayed activation of thoracic epidural anesthesia on plasma pro-atrial natriuretic peptide to indicate deviations in central blood volume during esophagectomy

BACKGROUND AND OBJECTIVES

A side effect to thoracic epidural anesthesia (TEA) is hypotension induced by central hypovolemia. This study addressed whether early activation (EA) versus late activation (LA) of TEA affects plasma pro-atrial natriuretic peptide (proANP) reflecting deviations in the central blood volume (CBV). We hypothesized that EA TEA would reduce plasma proANP, thus reflecting a decrease in CBV.

METHODS

A randomized, controlled, single-blinded trial was conducted. Patients undergoing open esophagectomy were randomized to EA (n=25, after induction of general anesthesia) or LA TEA (n=25, after re-established gastric continuity) with the epidural catheter placed at the interspaces Th7-8 or Th8-9. Plasma proANP was determined repetitively along with hemodynamic variables and administration of fluid/vasopressors as postoperative complications were noted.

RESULTS

With EA TEA, plasma proANP decreased following induction of anesthesia to the end of surgery (13%; 113±68 to 99±49 pmol/L; p=0.026), but that was not the case in the LA group (3%; 97±44 to 94±49 pmol/L; p=0.565) despite equal fluid balance (+1584±582 vs +1560±563 mL; p=0.888). Accordingly, the EA group required excessive treatment with vasopressors to maintain MAP >60 mm Hg during surgery (2.7±2 vs 1.6±1.4 ephedrine boluses; p=0.033 and infusion of phenylephrine for 216±86 vs 58±91 min; p<0.001). Plasma proANP and fluid balance were correlated only for EA patients (r=0.44; 95% CI 0.04 to 0.91; p=0.033).

CONCLUSIONS

EA TEA reduces plasma proANP indicating that CBV becomes affected. Based on a correlation between plasma proANP and fluid balance, a 2000 mL volume surplus of lactated Ringer's solution is required to maintain plasma proANP stable during open esophagectomy.

TRIAL REGISTRATION NUMBER

2014-002036-14 (https://www.clinicaltrialsregister.eu/ctr-search/search?query=2014-002036-14).

Plasma pro-atrial natriuretic peptide to estimate fluid balance during open and robot-assisted esophagectomy: a prospective observational study

Background

It remains debated how much fluid should be administered during surgery. The atrial natriuretic peptide precursor proANP is released by atrial distension and deviations in plasma proANP are reported associated with perioperative fluid balance. We hypothesized that plasma proANP would decrease when the central blood volume is compromised during the abdominal part of robot-assisted hybrid (RE) esophagectomy and that a positive fluid balance would be required to maintain plasma proANP.

Methods

Patients undergoing RE (n = 25) or open (OE; n = 25) esophagectomy for gastroesophageal cancer were included consecutively in this prospective observational study. Plasma proANP was determined repetitively during esophagectomy to allow for distinction between the abdominal and thoracic part of the procedure. The RE group was 15° head up tilted during the abdominal procedure.

Results

The blood loss was 250 (150–375) (RE) and 600 ml (390–855) (OE) (p = 0.01), but the two groups of patients were provided with a similar positive fluid balance: 1705 (1390–1983) vs. 1528 ml (1316–1834) (p = 0.4). However, plasma proANP decreased by 21% (p < 0.01) during the abdominal part of RE carried out during moderate head-up tilt, but only by 11% (p = 0.01) during OE where the patients were supine. Plasma proANP and fluid balance were correlated in the RE-group (r = 0.5 (0.073–0.840), p = 0.02) and tended to correlate in the OE group (r = 0.4 (−0.045–0.833), p = 0.08).

Conclusion

The results support that plasma proANP decreases when the central blood volume is compromised and suggest that an about 2200 ml surplus administration of crystalloid is required to maintain plasma proANP during esophagectomy.

Trial registration

Clinicaltrials.gov (NCT02077673). Registered retrospectively February 12^th 2014.