Pulse Pressure Variation Can Predict the Hemodynamic Response to Pneumoperitoneum in Dogs: A Retrospective Study

Abstract

Pneumoperitoneum may induce important hemodynamic alterations in healthy subjects. Pulse pressure variation (PPV) is a hemodynamic parameter able to discriminate preload dependent subjects. Anesthesia records of dogs undergoing laparoscopy were retrospectively evaluated. The anesthetic protocol included acepromazine, methadone, propofol and isoflurane administered with oxygen under mechanical ventilation. The hemodynamic parameters were considered five minutes before (BASE) and ten minutes after (P10) the pneumoperitoneum. Based on the cardiac index (CI) variation, at P10, dogs were classified as sensitive (S group, CI ≤ 15%) and non-sensitive (NO-S group). Data were analyzed with the ANOVA test and the ROC curve (p < 0.05). Fifty-five percent of dogs (S) had a reduction of CI ≥ 15% at P10 (2.97 ± 1.4 L/min/m2) compared to BASE (4.32 ± 1.62 L/min/m2) and at P10 in the NO-S group (4.51 ± 1.41 L/min/m2). PPV at BASE was significantly higher in the S group (22.4% ± 6.1%) compared to the NO-S group (10.9% ± 3.3%). The ROC curve showed a threshold of PPV > 16% to distinguish the S and NO-S groups. PPV may be a valid predictor of the hemodynamic response to pneumoperitoneum in dogs. A PPV > 16% can identify patients that may require fluid administration before the creation of pneumoperitoneum.

Effects of two alveolar recruitment maneuvers in an “open-lung” approach during laparoscopy in dogs

“…After induction of the pneumoperitoneum, in agreement with the literature, we found a significant increase in MAP in both groups, which could be explained by mechanical compression of the abdominal aorta, absorption of CO 2 with transient hypercapnia, and activation of renin–angiotensin–aldosterone axis with the production of neurohumoral factors, such as vasopressin ( 11 , 12 , 46 ). For this reason, an euvolemic preoperative volume status is important to minimize any cardiovascular depression associated with the pneumoperitoneum ( 7 , 42 , 50 ). Compression of the inferior vena cava reduces preload and is associated with the increase in afterload, which can lead to a decrease in CO, particularly in hypovolemic patients ( 46 , 49 ).…”

“…Compression of the inferior vena cava reduces preload and is associated with the increase in afterload, which can lead to a decrease in CO, particularly in hypovolemic patients ( 46 , 49 ). Several studies have shown that dogs with normal cardiovascular function can tolerate these variations of preload and afterload during laparoscopic surgery ( 42 ).…”

“…The accuracy of the signal was verified by a square wave test before starting the data collection ( 40 ). The cardiovascular parameters included in the monitoring have been SAP, MAP, DAP, SV, and CO ( 41 , 42 ). The data obtained were recorded and stored automatically every 3 s on a personal computer.…”

Laparoscopic versus Open Ovariectomy in Bitches: Changes in Cardiorespiratory Values, Blood Parameters, and Sevoflurane Requirements Associated with the Surgical Technique

“…At present, the prevention of the cardiovascular alterations is being thoroughly studied. In a recent publication, Di Bella et al [ 33 ] have shown that the pulse pressure variation can be a valid predictor of the hemodynamic response to laparoscopy in dogs. Moreover, it could be used to prevent the cardiac output reduction by allowing to optimize the fluid therapy before PNP.…”

“…In relation to the pathophysiological changes that may occur during the laparoscopic surgery both in human [ 19 , 20 , 30 , 31 , 32 ] and in veterinary medicine [ 17 , 21 , 24 , 33 , 34 ], numerous publications have thoroughly examined these potential alterations. Some studies on animals recorded effects in terms of cardiovascular [ 24 , 29 , 33 , 35 ], respiratory [ 17 , 25 , 26 , 27 , 34 , 36 ] and metabolic parameters [ 21 , 29 , 37 ].…”