Postmortem examinations of two calves with perforated abomasal ulceration

Postmortem findings in calf 1: Macroscopic examination revealed a severe, chronic, ulcerative abomasitis (two ulcers in pyloric region, one ulcer 3.5 cm in diameter with central perforation 1.5 cm in diameter (FIG 1); second ulcer 3 cm in diameter without perforation

(FIG 2). Hyperemia of the abomasal mucosa as well as edema of the abomasal wall was observed. Leakage of abomasal contents into the omental bursa had occurred, leading to severe bursitis omentalis with serosanguinous effusion.

Postmortem findings in calf 2: Severe, ulcerative and transmural abomasitis (two perforated ulcers in pyloric region, each 1 cm in diameter, with emergence of feed components into the abdominal cavity), in addition to severe edema and severe congestive hyperemia were diagnosed. Furthermore, a diffuse, consecutive, moderate to severe, fibrinopurulent peritonitis was found.

Table 1: Mean (± SD) respiratory rate, heart rate and the number of calves showing pale mucous membranes in the group of inhalation anesthesia (INH, n = 10), injection anesthesia (INJ, n = 9) and high-volume caudal epidural anesthesia (EPI, n = 8) one day prior to surgery (d -1) and on d 1 to 6 after surgery. * indicates a significant (P < 0.05) difference to baseline (d -1). Different letters denote a significant difference between groups (P < 0.05) at the specific point of time.

Respiratory rate

(breaths per min) d -1 d 1 d 2 d 3 d 4 d 5 d 6 Effect

INH mean 35.2 32.9 36.2 31.7 35.3 34.9 36.4 Time:

SD 6.1 7.9 9.5 7.9 9.3 10.0 11.0 P = 0.7400

INJ mean 34.9 34.8 33.9 34.1 33.8 36.3 37.7 Group:

SD 4.0 6.3 7.1 6.8 10.3 15.2 19.0 P = 0.8722

EPI mean 31.2 32.1 32.6 35.1 34.6 33.6 33.4 Time x Group:

SD 4.7 9.0 7.3 7.5 8.3 5.9 6.7 P = 0.8621

Heart rate (beats per min)

INH mean 104.9 118.4* 118.5* 120.6* 120.4* 121.6* 122.2* Time:

SD 13.5 17.7 16.1 11.9 12.4 9.8 11.2 P = < 0.0001

INJ mean 110.7 128.2* 128.8* 120.5* 124.4* 122.0* 120.9* Group:

SD 15.7 16.3 19.4 11.8 17.2 16.2 16.8 P = 0.7862

EPI mean 104.5 120.4* 120.3* 120.2* 123.7* 125.1* 129.2* Time x Group:

SD 13.8 8.9 10.8 9.6 15.1 11.9 10.7 P = 0.3390

Pale mucous membranes

INH n/N 0 / 10 3 / 10 2 / 10 0 / 10 0 / 10 0 / 10 0 / 10

INJ n/N 0 / 9 4 / 9* 1 / 9 2 / 9 1 / 9 2 / 9 1 / 9

EPI n/N 0 / 8 4 / 8* 1 / 8 2 / 8 1 / 8 0 / 8 0 / 8

overall n/N 0 / 27 11 / 27* 4 / 27 4 / 27 2 / 27 2 / 27 1 / 27

Table 2: Mean (± SD) red blood cell count (RBC), packed cell volume (PCV), hemoglobin (Hb) and platelets (PLT) in the group of inhalation anesthesia (INH, n = 10), injection anesthesia (INJ, n = 9) and high-volume caudal epidural anesthesia (EPI, n = 8) one day prior to surgery (d -1) and on day 1, 3 and 5 after surgery. * indicates significant (P < 0.05) difference to baseline (d -1). Different letters denote a significant difference between groups (P < 0.05) at the specific point of time.

RBC

Table 3: Median with 5 and 95% quantil (Q5/Q95) as well as minimum and maximum of serum pepsinogen concentrations in the group of inhalation anesthesia (INH, n = 10), injection anesthesia (INJ, n = 9) and high-volume caudal epidural anesthesia (EPI, n = 8) one day prior to surgery (d -1) and on d 1 to 5 after surgery. * indicates a significant (P < 0.05) difference to baseline (d -1). Different letters denote a significant difference between groups (P < 0.05) at the specific point of time.

Pepsinogen inhalation anesthesia (INH, n = 10), injection anesthesia (INJ, n = 9) and high-volume caudal epidural anesthesia (EPI, n = 8) one day prior to surgery (d -1) and on d 1 to 6 after surgery. * indicates a significant (P < 0.05) difference to baseline (d -1). Different letters denote a significant difference between groups (P < 0.05) at the specific point of time.

hemoFEC d -1 d 1 d 2 d 3 d 4 d 5 d 6

INH n/N 1 / 10 3 / 10 4 / 10 4 / 10 2 / 10 0 / 10 0 / 10

INJ n/N 1 / 9 5 / 9 4 / 9 2 / 9 4 / 9 2 / 9 1 / 9

EPI n/N 1 / 8 2 / 8 2 / 8 2 / 8 3 / 8 1 / 8 1 / 8

overall 3 / 27 10 / 27 10 / 27 8 / 27 9 / 27 3 / 27 2 / 27

Table 5: Frequency distribution of subsequent tests positive for occult blood in feces (hemoFEC) in the group of inhalation anesthesia (INH, n = 10), injection anesthesia (INJ, n = 9) and highvolume caudal epidural anesthesia (EPI, n = 8) from one day prior to surgery (d -1) to d 6 after surgery. * indicates a significant (P < 0.05) difference to baseline (d --1).

Different letters denote a significant difference between groups (P < 0.05) at the specific point of time.

Table 6: Mean (± SD) total energy intake and daily weight gain in hemoFEC-positive (two or more subsequent positive tests for occult blood in feces, n = 14) and hemoFEC-negative (one or no positive test for occult blood in feces, n = 12) calves, pre op (averaged data from d -5 to -1) and post op (averaged data from d 1 to 6). * indicates significant (P < 0.05) difference to baseline (d -1). Different letters denote a significant difference between groups (P < 0.05) at the specific point of time.

Table 7: Mean (± SD) red blood cell count (RBC) and packed cell volume (PCV) in hemoFEC-positive (two or more subsequent positive tests for occult blood in feces, n = 14) and hemoFEC-negative (one or no positive test for occult blood in feces, n = 12) calves, one day prior to surgery (d -1) and on d 1, 3 and 5 after surgery. * indicates significant (P < 0.05) difference to baseline (d -1). Different letters denote a significant difference between groups (P < 0.05) at the specific point of time.

RBC serum pepsinogen concentrations in hemoFEC-positive (two or more subsequent positive tests for occult blood in feces, n = 14) and hemoFEC-negative (one or no positive test for occult blood in feces, n = 12) calves one day prior to surgery (d -1) and on d 1 to 5 after surgery. * indicates a significant (P < 0.05) difference to baseline (d -1). Different letters denote a significant difference between groups (P < 0.05) at the specific point of time.

Pepsinogen

(perforated abomasal ulcer, died on d 5 after umbilical surgery), calf 3 (tentative diagnosis of bleeding abomasal ulceration) and the frequency of the accordant finding in the 26 remaining calves of the study one day prior to surgery (d -1) and on d 1 to 6 after surgery.

* indicates a significant (P < 0.05) difference to baseline (d -1).

Calf 1 Calf 2 Calf 3 Remaining calves (n = 26)

day -1 1 2 3 4 5 6 -1 1 2 3 4 5 -1 1 2 3 4 5 6 -1 1 2 3 4 5 6

arched back + + + + + + 0 2 1 0 1 1 0

strained abdominal wall + + + + + + 0 8* 5 3 1 0 0

obtund behavior + + + + + + + + + + + + + + + 0 15* 10* 4 4 3 3

head hanging down + + + + 0 0 0 0 0 1 0

muzzle into/over water + + + + 0 0 0 0 0 0 0

teeth grinding + + + 0 2 0 1 1 1 1

reduced milk intake + + + + + + + + + + 0 1 2 5 1 2 1

pale mucous membranes + + + + + + + + + + 0 11* 7* 2 1 1 0

diarrhea + + + + + + + + + + + + 0 6* 6* 8* 4 3 1

melena + + 0 0 0 0 0 0 0

positive abdominal ballottement + + + + + + + 0 0 0 0 0 0 0

positive abdominal percussion + + 0 0 0 0 0 0 0

distended sublumbar fossa + + 0 2 1 1 0 1 1

distended ventral abdomen + 0 0 1 0 1 0 0

+ indicates the existence of the accordant finding in calf 1, 2 and 3.

Red blood cell count (RBC), packed cell volume (PCV), hemoglobin (Hb), platelets (PLT), serum pepsinogen concentration and test for occult blood in feces (hemoFEC) in calf 1 (perforated abomasal ulcer, euthanized during re-laparotomy on d 6 after umbilical surgery), calf 2 (perforated abomasal ulcer, died on d 5 after umbilical surgery), calf 3 (tentative diagnosis of bleeding abomasal ulceration) and mean (±SD) values of the 26 remaining calves of the study one day prior to surgery (d -1) and on d 1 to 5 after surgery.

* indicates a significant (P < 0.05) difference to baseline (d -1).

Calf 1 Calf 2 Calf 3 Remaining calves (n= 26)

+ = positive result of test for occult blood in feces. - = negative result of test for occult blood in feces. For remaining calves, number of positive hemoFEC-tests is presented in %. Serum pepsinogen concentrations are presented as median with 5 and 95% quantil (Q5/Q95).

Figure 1: Perforated abomasal ulcer, opening into the omental bursa (calf 1)

Figure 2: Nonperforated abomasal ulcer (calf 1), hyperemia and edema of the abomasal wall

4.5. Discussion

The objective of this study was to evaluate the impact of umbilical surgery under inhalation anesthesia, injection anesthesia or high-volume caudal epidural anesthesia on the development of bleeding abomasal lesions in calves.

Mild gastrointestinal bleeding was diagnosed by subsequent positive tests for occult blood in feces in approximately 30% of the calves between d 1 and 4 after surgery. These findings were independent of the anesthetic regime and the calves did not show any clinical or hematological signs of blood loss. Moreover, hemoFEC-detected bleeding did not have significant impact on postoperative recovery in the form of feed intake and daily weight gain.

Offinger (2010) demonstrated that the intraoperative stress response due to cardiorespiratory depression in the current study population was significantly higher in INJ compared to INH and EPI group. A difference between groups could also be shown for postoperative feed intake and daily weight gain, which was lowest in INJ group presumably caused by more pronounced pulmonary affection (Chapter 1). However, results of the current study indicate that a disturbance of gastrointestinal integrity after surgical intervention does not occur subjected to the anesthetic regime used. Statistical analysis of parameters indicating gastrointestinal damage and bleeding respectively, (haematology, tests for occult blood in feces, color of mucous membranes, serum pepsinogen concentration, RR, HR,) did not reveal significant differences between the anesthetic groups (Tables 1 to 5).

The value of hematology and tests for occult blood in feces for diagnosis of abomasal ulcers depends on the type of ulceration. Bleeding ulcers (Type II), if associated with severe blood loss, are likely to cause a decrease in PCV, Hb (OK et al. 2001), RBC, and PLT as well as positive results in tests for occult blood in feces. The mild decrease in RBC, PCV, Hb and PLT observed in all calves of the study between d – 1 and 1 (Tables 2 and 10) can be explained by inevitable blood loss due to circumstances of surgery (OFFINGER 2010).

In calf 3 hematology revealed an evident decrease in RBC, PCV, Hb and PLT between d 3 and 5 after surgery. Moreover, tests for occult blood were continuously positive between d 1

and 5 (Table 10). Theses findings led to tentative diagnosis of bleeding ulceration, which was supported by clinical signs (Table 9).

In calf 1 there was no comparable decrease in RBC, PCV, Hb and PLT after d 1. These parameters were reduced from the start of documentation (day before surgery (d -1)).

Furthermore, tests for occult blood in feces revealed intermittent positive results (d 1, 3 and 5 after surgery, Table 10). These findings may be explained by the presence of an ulcer type II at the beginning of the study, which was clinically unapparent (no pale mucous membranes, no melena, Table 9).

In contrast, hematology and tests for occult blood in feces are considered inconclusive of perforating ulceration as long as severe bleeding is absent. Ulcers that are only mild or not bleeding may perforate (Type III or IV) without influencing hematology or fecal tests as seen in calf 2 of the current report (Table 10).

It is remarkable that approximately one third of the remaining calves of the study, which were clinically unapparent regarding signs of abomasal ulceration (n = 26), were positive in tests for occult blood in feces between d 1 and 4 (Table 10). These calves did not show alarming changes in haematology and left the study clinically healthy. Statistical analysis revealed that the parameters feed intake and daily weight gain in calves with two or more subsequent positive tests for occult blood were not statistically different to calves with only one or no positive test (Table 6). Consequently the test for occult blood in feces may sensitively indicate bleeding in the gastrointestinal tract but can not, by itself, provide prognostic predication for the affected calf.

Moreover, serum pepsinogen concentration was determined in all calves of the study (Table 3) (DORNY and VERCRUYSSE 1998). In human medicine, serum pepsinogen is used as an indicator for mucosal damage (LORENTE et al. 2002, GOMEZ et al. 2006). In veterinary medicine, pepsinogen is primarily used in diagnostic investigation of ostertagiosis (BERGHEN et al. 1993). According to MESARIC (2005), high pepsinogen concentrations (>

5.0 UL^-1) may also be an indication of severe abomasal ulceration in cattle, with a correlation between the number and especially the extent of the lesions and pepsinogen concentration.

Additionally, the sensitivity of pepsinogen is presumed to be higher in diffuse mucosal

damage (as e.g. in ostertagiosis) than with circumscriptive lesions such as isolated ulcers. As pepsinogen values of calves 1, 2 and 3 were low (< 3.0 U/L) at any time and positive calves did not have higher pepsinogen concentrations in comparison to hemoFEC-negative calves (Table 8), the validity of pepsinogen in ulcer diagnosis could not be confirmed in this study.

In contrast to the positive postoperative development in the majority of calves two cases of perforated abomasal ulceration (calves 1 and 2, Tables 9 and 10) occurred during postoperative study period. These calves showed particularly severe clinical symptoms similar to a third calf with tentative diagnosis of bleeding ulceration (Table 9).

Clinical signs of gastrointestinal lesions in these cases may have been influenced by the effects of the preceding umbilical surgery and therefore may have been less obvious.

However, several characteristic clinical symptoms were present:

The obtund to apathetic behaviour and posture such as an arched back and a drooping head shown by the current calves have also been described by other authors as symptoms for perforating abomasal ulcers (HAWKINS et al. 1986, MUELLER et al. 1999, DIRKSEN 1994, RADEMACHER and LORCH 2001). The habit of calf 2 to place its muzzle into water, which is considered to be a sign of severe abdominal pain, has also been previously described in calves with perforating ulcers (RADEMACHER and LORCH 2001). Teeth grinding, a further indication of pain, was noticed in calf 1 (also in HAWKINS et al. 1986). Typical signs of colic, like flank watching or kicking at the abdomen are only sporadically observed in association with perforating ulceration (HAWKINS et al. 1986, 10% in RADEMACHER and LORCH 2001). Neither calves 1 and 2, with confirmed perforated ulcers, showed accordant behaviour. Signs of dehydration (calf 1), succussion sounds revealed by ballottement and pale mucous membranes (calves 1 and 2) were found in the current cases as well as in other reports (RADEMACHER and LORCH 2001, HAWKINS et al. 1986 and MUELLER et al.

1999). In calf 2 left displacement of the abomasum was diagnosed as it was the case in 70%

of calves with perforated abomasal ulceration described by RADEMACHER and LORCH (2001). Hence, signs of displaced abomasum may refer to coexistent perforating ulceration.

Symptoms such as strained abdominal wall and defence reaction to palpation of the ventral abdomen, both described as indicative of perforated ulceration (RADEMACHER and LORCH 2001, MUELLER et al. 1999) may have been of limited validity here, due to the presence of the surgical wound. Data reported for rectal temperature, RR and HR vary in the current cases as well as in other reports, thus allowing no conclusion regarding diagnostic evidence.

The calf with tentative bleeding ulceration (calf 3) showed clinical signs of abdominal pain comparable to calves 1 and 2 (e.g. strained abdominal wall, obtund behaviour, abnormal posture, teeth grinding, the habit to place the muzzle into water as well as reduced milk intake) and additionally, signs of anemia (pale mucous membranes for multiple days and particularly melena), which suggested the presence of clinical gastrointestinal bleeding, more precisely bleeding abomasal ulceration.

In post-mortem examinations of calves 1 and 2 severe ulcerative abomasitis with one (calf 1, Figure 1 and 2) or two (calf 2) perforated ulcers, respectively, was found. In both cases the ulcers were located in the pyloric region which is considered to be typical (WELCHMAN and BAUST 1987, DIRKSEN 1994, RADEMACHER and LORCH 2001). Perforation into the omental bursa (calf 1) is also a common finding (DIRKSEN 1994, RADEMACHER and LORCH 2001). Earlier reports confirm that, if ulcers perforate, leakage of abomasal contents into the abdominal cavity leads to a prompt development of peritonitis; perforation into the omental bursa or adhesions to adjacent surfaces may initially delay the course of disease (HAWKINS et al. 1984, DIRKSEN 1994, MUELLER et al. 1999, RADEMACHER and LORCH 2001). As peritonitis in both calves of the current report was severe and diffuse, ulceration was categorized as Type IV in both cases.

The causes of subclinical gastrointestinal bleeding and apparent abomasal ulceration in the present study are presumed to be multifactorial. The percentage of 3 of 29 calves being affected and the fact that an impact of anesthetic regimes could not be detected suggests that circumstances associated with the event of surgery had significant impact on ulcer formation.

Endocrine effects of stress, like inhibition of prostaglandin-synthesis and therewith hypersecretion of acid and pepsin and reduced secretion of mucus, disturb mucosal

homeostasis and are hence considered to be ulcer promoting (LILLEY et al. 1985, GEISHAUSER 1989, BRAUN et al. 1991). In the current cases stressors associated with the study regime (transport, change of housing, handling, blood sampling) and particularly umbilical surgery and wound pain affected the calves. Offinger (2010) demonstrated that calves of the current study population showed considerable stress during umbilical surgery.

An earlier report describes the occurrence of perforating abomasal ulceration in a calf after the painful intervention of dehorning (GEISHAUSER 1989).

Furthermore, non-steroidal anti-inflammatory drugs (NSAIDs) are known to have an irritating effect on gastrointestinal mucosa by reducing mucosal perfusion due to prostaglandin inhibition. The non-specific COX-inhibitor flunixin-meglumine caused gastric mucosal lesions in foals (TRAUB-DARGATZ et al. 1988) and dogs (DOW et al. 1990) and was administered to calves of the present report for three days (manufacturer’s recommendation).

Hence, it might play a role in current ulcer development.

A further considerable factor on abomasal mucosa is diet, especially due to its impact on abomasal pH. Ahmed et al. (2002a) state that fasting or low frequency feeding leads to low abomasal luminal pH, which promotes proteolytic activity and might therefore facilitate ulcer formation. In the present study, feed was withheld 12 h before surgery, which is a common procedure applied to calves (KEEGAN et al. 2006, SUTRADAR et al. 2009) to reduce intraoperative risks such as pressure on diaphragm and regurgitation. As abomasal emptying in calves takes approximately 12 h and flow rate decreases with time (after 7 h 80% of milk passed the abomasum, GAUDREAU and BRISSON 1980) a shorter fasting period is presumed to reduce intraoperative risks to an adequate degree and appears to be more reasonable regarding ulcer prevention. Furthermore, prophylactic or therapeutic administration of antacids (Al(OH)3, Mg(OH)2) (AHMED 2002), histamine-receptor-antagonists (cimetidine, ranitidine) (DIRKSEN 1994, AHMED 2001) or proton-pump inhibitors (omeprazole) (AHMED 2005) may help to stabilize abomasal pH but this was not investigated in the present study.

Conclusions and Clinical relevance According to tests for occult blood in feces the prevalence of gastrointestinal bleeding in calves does increase after surgery, though, independent of the anesthetic regime used. These bleedings are considered to be mild as no

impact on haematological or clinical parameters could be assessed and feed intake as well as daily weight gain remained unaffected. Cases of clinical apparent abomasal lesions described here indicate that clinical signs like posture and behaviour are more valuable for diagnosis of perforating ulcers than laboratory parameters. Perforating ulcers without serious bleeding can not be diagnosed by means of haematology or tests for occult blood in feces. Regarding bleeding ulcers, laboratory parameters are a reasonable addition to clinical examination. As a considerably high percentage of calves, namely 3 of 29, developed clinically apparent abomasal ulceration, it is presumed that the effects of surgical intervention increase the risk for abomasal ulcers in calves. It is therefore considered reasonable to minimize these influences by prevention of stress, short preoperative fasting periods, high frequency feeding of small volumes and oral application of antacids.

5. Schlussbetrachtung

In der dieser Arbeit zugrunde liegenden Studie wurden die Auswirkungen einer Inhalationsnarkose, einer Injektionsanästhesie und einer hohen Epiduralanästhesie auf die postoperative Entwicklung von Kälbern nach einer Nabeloperation vergleichend untersucht.

Dabei konnte gezeigt werden, dass die Kälber in Abhängigkeit von den Anästhesieverfahren postoperativ signifikant (Signifikanzgrenze: P < 0,05) unterschiedliche Gewichtszunahmen aufwiesen. Die Kälber der INH Gruppe (operiert unter Inhalationsnarkose mittels Isofluran) zeigten gegenüber den Kälbern der INJ Gruppe (operiert unter Anästhesie mittels IM Injektion von Xylazin und IV Injektion von Ketamin) signifikant höhere Gewichtszunahmen während der ersten sechs Tage post operationem. Korrespondierend zu den schlechteren Gewichtszunahmen in der INJ Gruppe war bei diesen Kälbern auch die Futteraufnahme während dieser Zeit signifikant niedriger im Vergleich zu dem vor der Operation ermittelten Basiswert, während sich die Futteraufnahme in der INH und der EPI Gruppe (operiert unter Epiduralanästhesie mittels Xylazin und Procain) im postoperativen Zeitraum nicht signifikant verringerte.

Die unterschiedliche Gewichtsentwicklung der Kälber nach der Operation in Abhängigkeit von dem verwendeten Anästhesieverfahren spiegelte sich auch im Verhalten der Tiere wieder.

Das zur Beurteilung des Verhaltens verwendete Bewertungssystem MPDS erwies sich dabei als gut geeignet, um das unterschiedliche Ausmaß an gezeigtem Schmerz- und Komfortverhalten zu objektivieren und zu quantifizieren. Die Kälber der INJ Gruppe zeigten in dem Zeitraum von 36 Stunden post operationem bis zum 5. Tag nach der Operation signifikant höhere MPDS-Werte als die Tiere der INH Gruppe und auch tendenziell höhere Werte als die Kälber der EPI Gruppe.

Eine mögliche Ursache für verringerte Futteraufnahmen, geringe Gewichtszunahmen und laut MPDS gedämpftem Verhalten bei den Kälbern der INJ Gruppe könnte eine durch Wundschmerz ausgelöste, stressbedingte Depression sein (ANDERSON u. MUIR 2005).

Schmerz löst eine Stressreaktion unter Aktivierung des hypothalamo-hypophysär-adrenergen Systems aus und bewirkt somit eine erhöhte Kortisolausschüttung, weshalb Kortisol in zahlreichen Studien als Indikator für Schmerz verwendet wird (MELLOR et al. 2002;

ANDERSON u. MUIR 2005). In einigen Studien konnten bis zu mehreren Tage nach einer Kastration von Kälbern erhöhte Blutkortisolwerte festgestellt werden (TING et al. 2003;

PANG et al. 2006; STILWELL et al. 2008), während in anderen Studien die Kortisolkonzentrationen bei Kälbern bereits zwei bis drei Stunden nach einer Kastration (THUER et al. 2007) die Basiswerte erreichten. Die Kortisolsekretion unterliegt verschiedenen Einflüssen wie Alter, Handling und Haltungsbedingungen (MOLONY u.

KENT 1997; VALVERDE u. GUNKEL 2005) sowie zirkadianen Rhythmen (LEFCOURT et al. 1993), weshalb die Aussagekraft von Kortisol als Indikator für Schmerz umstritten ist.

Obwohl in der vorliegenden Studie versucht wurde entsprechende Einflüsse möglichst zu minimieren (Probennahmen zur gleichen Tageszeit, ähnliches Alter der Kälber, gleiche Gewöhnung an die Umweltbedingungen) unterlagen die Messungen der Kortisolkonzentrationen einer großen Streuung. Die Mittelwerte waren bis zum fünften Tag nach der Operation tendenziell aber nicht signifikant erhöht, wobei sich keine Unterschiede zwischen den Anästhesiegruppen ergaben. Die makroskopische und palpatorische Beurteilung der Wunde ergab keinerlei Anzeichen dafür, dass in der INJ Gruppe, verglichen mit den anderen Gruppen, eine schlechtere Wundheilung oder vermehrter Wundschmerz als mögliche Ursache für die schlechtere Entwicklung in dieser Gruppe vorlag.

Die klinische Untersuchung der Kälber hingegen gab Hinweise darauf, dass der unterschiedlichen postoperativen Entwicklung eine unterschiedlich starke Beeinträchtigung der Lungengesundheit zugrunde lag. So zeigten die Kälber aus der INJ Gruppe die tendenziell höchsten Werte im respiratorischen- und Auskultationsscore. Gleichzeitig war auch die Rektaltemperatur und die Anzahl der erforderlichen Antibiotikabehandlungen im postoperativen Zeitraum in der INJ Gruppe, im Vergleich zu INH und EPI Gruppe, am höchsten. Hieraus wird geschlossen, dass sich die Anästhesieverfahren unterschiedlich auf die Lungenfunktion auswirken, damit die Lungengesundheit auch nachhaltig beeinflussen und somit unterschiedliche Auswirkungen auf die postoperative Entwicklung der Kälber zur Folge haben.

Es ist bekannt, dass in Folge der Rückenlage (KLEIN und FISHER 1988; WAGNER et al.

Es ist bekannt, dass in Folge der Rückenlage (KLEIN und FISHER 1988; WAGNER et al.

Im Dokument Einfluss einer Inhalationsnarkose, Injektionsanästhesie und hohen Epiduralanästhesie auf die postoperative Entwicklung von Kälbern (Seite 46-83)